diff --git a/composer.json b/composer.json
index 63b08d9a2d4..e09e177396f 100644
--- a/composer.json
+++ b/composer.json
@@ -17,22 +17,23 @@
     "require-dev": {
         "behat/mink": "^1.8",
         "behat/mink-goutte-driver": "^1.2",
+        "behat/mink-browserkit-driver": "dev-SF5 as v1.3.4",
         "behat/mink-selenium2-driver": "^1.4",
         "composer/composer": "^1.9.1",
         "drupal/coder": "^8.3.7",
         "mikey179/vfsstream": "^1.6.8",
         "phpunit/phpunit": "^8.4.1",
         "phpspec/prophecy": "^1.7",
-        "symfony/css-selector": "^4.4",
+        "symfony/css-selector": "^4.4|^5.1",
         "symfony/phpunit-bridge": "^5.1.4",
         "symfony/var-dumper": "^5.1.2",
-        "symfony/error-handler": "^4.4",
+        "symfony/error-handler": "^4.4|^5.1",
         "justinrainbow/json-schema": "^5.2",
-        "symfony/filesystem": "^4.4",
-        "symfony/finder": "^4.4",
-        "symfony/lock": "^4.4",
-        "symfony/browser-kit": "^4.4",
-        "symfony/dom-crawler": "^4.4 !=4.4.5",
+        "symfony/filesystem": "^4.4|^5.1",
+        "symfony/finder": "^4.4|^5.1",
+        "symfony/lock": "^4.4|^5.1",
+        "symfony/browser-kit": "^4.4|^5.1",
+        "symfony/dom-crawler": "^4.4|^5.1 !=4.4.5",
         "easyrdf/easyrdf": "^0.9"
     },
     "replace": {
@@ -101,6 +102,10 @@
         "phpcbf": "phpcbf --standard=core/phpcs.xml.dist --runtime-set installed_paths $($COMPOSER_BINARY config vendor-dir)/drupal/coder/coder_sniffer --"
     },
     "repositories": [
+        {
+            "type": "vcs",
+            "url": "https://github.com/mdlutz24/MinkBrowserKitDriver.git"
+        },
         {
             "type": "composer",
             "url": "https://packages.drupal.org/8"
diff --git a/composer.lock b/composer.lock
index e75dc069854..fca9c270c69 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
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         "This file is @generated automatically"
     ],
-    "content-hash": "8877ebb73b0fca58e145989738ba04b4",
+    "content-hash": "e1837fbf4848d5dee7eff257230b9aaf",
     "packages": [
         {
             "name": "asm89/stack-cors",
@@ -183,16 +183,10 @@
                 "zend",
                 "zikula"
             ],
-            "funding": [
-                {
-                    "url": "https://packagist.com",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
-                    "type": "tidelift"
-                }
-            ],
+            "support": {
+                "issues": "https://github.com/composer/installers/issues",
+                "source": "https://github.com/composer/installers/tree/v1.9.0"
+            },
             "time": "2020-04-07T06:57:05+00:00"
         },
         {
@@ -386,20 +380,6 @@
                 "parser",
                 "php"
             ],
-            "funding": [
-                {
-                    "url": "https://www.doctrine-project.org/sponsorship.html",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://www.patreon.com/phpdoctrine",
-                    "type": "patreon"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/doctrine%2Flexer",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-05-25T17:44:05+00:00"
         },
         {
@@ -722,18 +702,21 @@
             "license": [
                 "GPL-2.0-or-later"
             ],
-            "description": "Drupal is an open source content management platform powering millions of websites and applications.",
-            "transport-options": {
-                "relative": true
-            }
+            "description": "Drupal is an open source content management platform powering millions of websites and applications."
         },
         {
             "name": "drupal/core-project-message",
             "version": "9.1.x-dev",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/drupal/core-project-message.git",
+                "reference": "812d6da43dd49cc210af62e80fa92189e68e565a"
+            },
             "dist": {
-                "type": "path",
-                "url": "composer/Plugin/ProjectMessage",
-                "reference": "b4efdbe26634b41a1b89e4f3770a8074769088a6"
+                "type": "zip",
+                "url": "https://api.github.com/repos/drupal/core-project-message/zipball/812d6da43dd49cc210af62e80fa92189e68e565a",
+                "reference": "812d6da43dd49cc210af62e80fa92189e68e565a",
+                "shasum": ""
             },
             "require": {
                 "composer-plugin-api": "^1.1 || ^2",
@@ -755,18 +738,21 @@
             "homepage": "https://www.drupal.org/project/drupal",
             "keywords": [
                 "drupal"
-            ],
-            "transport-options": {
-                "relative": true
-            }
+            ]
         },
         {
             "name": "drupal/core-vendor-hardening",
             "version": "9.1.x-dev",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/drupal/core-vendor-hardening.git",
+                "reference": "71df53f24d54c464ac18762a530fc7c3bf131a7f"
+            },
             "dist": {
-                "type": "path",
-                "url": "composer/Plugin/VendorHardening",
-                "reference": "d54f0b3cc8b4237f3a41a0860a808db242f9da9e"
+                "type": "zip",
+                "url": "https://api.github.com/repos/drupal/core-vendor-hardening/zipball/71df53f24d54c464ac18762a530fc7c3bf131a7f",
+                "reference": "71df53f24d54c464ac18762a530fc7c3bf131a7f",
+                "shasum": ""
             },
             "require": {
                 "composer-plugin-api": "^1.1 || ^2",
@@ -788,10 +774,7 @@
             "homepage": "https://www.drupal.org/project/drupal",
             "keywords": [
                 "drupal"
-            ],
-            "transport-options": {
-                "relative": true
-            }
+            ]
         },
         {
             "name": "egulias/email-validator",
@@ -1126,12 +1109,6 @@
                 "psr-17",
                 "psr-7"
             ],
-            "funding": [
-                {
-                    "url": "https://funding.communitybridge.org/projects/laminas-project",
-                    "type": "community_bridge"
-                }
-            ],
             "time": "2020-07-07T15:34:31+00:00"
         },
         {
@@ -1248,12 +1225,6 @@
                 "feed",
                 "laminas"
             ],
-            "funding": [
-                {
-                    "url": "https://funding.communitybridge.org/projects/laminas-project",
-                    "type": "community_bridge"
-                }
-            ],
             "time": "2020-08-18T13:45:04+00:00"
         },
         {
@@ -1304,12 +1275,6 @@
                 "laminas",
                 "stdlib"
             ],
-            "funding": [
-                {
-                    "url": "https://funding.communitybridge.org/projects/laminas-project",
-                    "type": "community_bridge"
-                }
-            ],
             "time": "2020-08-25T09:08:16+00:00"
         },
         {
@@ -1362,12 +1327,6 @@
                 "laminas",
                 "zf"
             ],
-            "funding": [
-                {
-                    "url": "https://funding.communitybridge.org/projects/laminas-project",
-                    "type": "community_bridge"
-                }
-            ],
             "time": "2020-08-18T16:34:51+00:00"
         },
         {
@@ -2071,20 +2030,6 @@
             ],
             "description": "Symfony Console Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T07:39:58+00:00"
         },
         {
@@ -2142,20 +2087,6 @@
             ],
             "description": "Symfony Debug Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-10T07:47:39+00:00"
         },
         {
@@ -2229,20 +2160,6 @@
             ],
             "description": "Symfony DependencyInjection Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T09:56:45+00:00"
         },
         {
@@ -2300,20 +2217,6 @@
             ],
             "description": "Symfony ErrorHandler Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T09:56:45+00:00"
         },
         {
@@ -2384,20 +2287,6 @@
             ],
             "description": "Symfony EventDispatcher Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-13T14:18:44+00:00"
         },
         {
@@ -2460,20 +2349,6 @@
                 "interoperability",
                 "standards"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-06T13:19:58+00:00"
         },
         {
@@ -2529,20 +2404,6 @@
             ],
             "description": "Symfony HttpFoundation Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T07:39:58+00:00"
         },
         {
@@ -2634,20 +2495,6 @@
             ],
             "description": "Symfony HttpKernel Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-09-02T08:09:29+00:00"
         },
         {
@@ -2711,20 +2558,6 @@
                 "mime",
                 "mime-type"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T10:01:29+00:00"
         },
         {
@@ -2787,20 +2620,6 @@
                 "polyfill",
                 "portable"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-14T12:35:20+00:00"
         },
         {
@@ -2864,20 +2683,6 @@
                 "portable",
                 "shim"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-14T12:35:20+00:00"
         },
         {
@@ -2949,20 +2754,6 @@
                 "portable",
                 "shim"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-04T06:02:08+00:00"
         },
         {
@@ -3030,20 +2821,6 @@
                 "portable",
                 "shim"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-14T12:35:20+00:00"
         },
         {
@@ -3107,20 +2884,6 @@
                 "portable",
                 "shim"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-14T12:35:20+00:00"
         },
         {
@@ -3187,20 +2950,6 @@
                 "portable",
                 "shim"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-14T12:35:20+00:00"
         },
         {
@@ -3250,20 +2999,6 @@
             ],
             "description": "Symfony Process Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-23T08:31:43+00:00"
         },
         {
@@ -3328,20 +3063,6 @@
                 "psr-17",
                 "psr-7"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-06-25T08:21:47+00:00"
         },
         {
@@ -3418,20 +3139,6 @@
                 "uri",
                 "url"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-10T07:27:51+00:00"
         },
         {
@@ -3514,20 +3221,6 @@
             ],
             "description": "Symfony Serializer Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-30T07:21:38+00:00"
         },
         {
@@ -3590,20 +3283,6 @@
                 "interoperability",
                 "standards"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-06T13:23:11+00:00"
         },
         {
@@ -3680,20 +3359,6 @@
             ],
             "description": "Symfony Translation Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
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-            ],
             "time": "2020-08-17T09:56:45+00:00"
         },
         {
@@ -3755,20 +3420,6 @@
                 "interoperability",
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-            "funding": [
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-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
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-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-06T13:23:11+00:00"
         },
         {
@@ -3862,20 +3513,6 @@
             ],
             "description": "Symfony Validator Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-21T09:47:32+00:00"
         },
         {
@@ -3952,20 +3589,6 @@
                 "debug",
                 "dump"
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-            "funding": [
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-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
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-                    "type": "github"
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-                    "type": "tidelift"
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-            ],
             "time": "2020-08-17T07:42:30+00:00"
         },
         {
@@ -4025,20 +3648,6 @@
             ],
             "description": "Symfony Yaml Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
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-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
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             "time": "2020-08-26T08:30:46+00:00"
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         {
@@ -4104,16 +3713,6 @@
             "keywords": [
                 "templating"
             ],
-            "funding": [
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/twig/twig",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-05T15:09:04+00:00"
         },
         {
@@ -4231,23 +3830,23 @@
         },
         {
             "name": "behat/mink-browserkit-driver",
-            "version": "v1.3.4",
+            "version": "dev-SF5",
             "source": {
                 "type": "git",
-                "url": "https://github.com/minkphp/MinkBrowserKitDriver.git",
-                "reference": "e3b90840022ebcd544c7b394a3c9597ae242cbee"
+                "url": "https://github.com/mdlutz24/MinkBrowserKitDriver.git",
+                "reference": "dc566b2cb383a4f09907d3586a80281d8ac0f453"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/minkphp/MinkBrowserKitDriver/zipball/e3b90840022ebcd544c7b394a3c9597ae242cbee",
-                "reference": "e3b90840022ebcd544c7b394a3c9597ae242cbee",
+                "url": "https://api.github.com/repos/mdlutz24/MinkBrowserKitDriver/zipball/dc566b2cb383a4f09907d3586a80281d8ac0f453",
+                "reference": "dc566b2cb383a4f09907d3586a80281d8ac0f453",
                 "shasum": ""
             },
             "require": {
                 "behat/mink": "^1.7.1@dev",
                 "php": ">=5.3.6",
-                "symfony/browser-kit": "~2.3|~3.0|~4.0",
-                "symfony/dom-crawler": "~2.3|~3.0|~4.0"
+                "symfony/browser-kit": "~2.3|~3.0|~4.0|~5.0",
+                "symfony/dom-crawler": "~2.3|~3.0|~4.0|~5.0"
             },
             "require-dev": {
                 "mink/driver-testsuite": "dev-master",
@@ -4265,7 +3864,11 @@
                     "Behat\\Mink\\Driver\\": "src/"
                 }
             },
-            "notification-url": "https://packagist.org/downloads/",
+            "autoload-dev": {
+                "psr-4": {
+                    "Behat\\Mink\\Tests\\Driver\\": "tests"
+                }
+            },
             "license": [
                 "MIT"
             ],
@@ -4284,7 +3887,10 @@
                 "browser",
                 "testing"
             ],
-            "time": "2020-03-11T09:49:45+00:00"
+            "support": {
+                "source": "https://github.com/mdlutz24/MinkBrowserKitDriver/tree/SF5"
+            },
+            "time": "2020-09-21T18:40:47+00:00"
         },
         {
             "name": "behat/mink-goutte-driver",
@@ -4456,20 +4062,6 @@
                 "ssl",
                 "tls"
             ],
-            "funding": [
-                {
-                    "url": "https://packagist.com",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/composer",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-23T12:54:47+00:00"
         },
         {
@@ -4547,20 +4139,6 @@
                 "dependency",
                 "package"
             ],
-            "funding": [
-                {
-                    "url": "https://packagist.com",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/composer",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-03T09:35:19+00:00"
         },
         {
@@ -4621,20 +4199,6 @@
                 "spdx",
                 "validator"
             ],
-            "funding": [
-                {
-                    "url": "https://packagist.com",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/composer",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-15T15:35:07+00:00"
         },
         {
@@ -4679,20 +4243,6 @@
                 "Xdebug",
                 "performance"
             ],
-            "funding": [
-                {
-                    "url": "https://packagist.com",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/composer",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-19T10:27:58+00:00"
         },
         {
@@ -4749,20 +4299,6 @@
                 "constructor",
                 "instantiate"
             ],
-            "funding": [
-                {
-                    "url": "https://www.doctrine-project.org/sponsorship.html",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://www.patreon.com/phpdoctrine",
-                    "type": "patreon"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/doctrine%2Finstantiator",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-05-29T17:27:14+00:00"
         },
         {
@@ -5137,12 +4673,6 @@
                 "object",
                 "object graph"
             ],
-            "funding": [
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/myclabs/deep-copy",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-06-29T13:22:24+00:00"
         },
         {
@@ -5790,16 +5320,6 @@
                 "testing",
                 "xunit"
             ],
-            "funding": [
-                {
-                    "url": "https://phpunit.de/donate.html",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/sebastianbergmann",
-                    "type": "github"
-                }
-            ],
             "time": "2020-06-22T07:06:58+00:00"
         },
         {
@@ -6464,16 +5984,6 @@
                 "parser",
                 "validator"
             ],
-            "funding": [
-                {
-                    "url": "https://github.com/Seldaek",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/seld/jsonlint",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-25T06:56:57+00:00"
         },
         {
@@ -6628,20 +6138,6 @@
             ],
             "description": "Symfony BrowserKit Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-05-22T17:28:00+00:00"
         },
         {
@@ -6695,20 +6191,6 @@
             ],
             "description": "Symfony CssSelector Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-07-05T09:39:30+00:00"
         },
         {
@@ -6770,20 +6252,6 @@
             ],
             "description": "Symfony DomCrawler Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-12T06:20:35+00:00"
         },
         {
@@ -6834,20 +6302,6 @@
             ],
             "description": "Symfony Filesystem Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-21T17:19:37+00:00"
         },
         {
@@ -6897,20 +6351,6 @@
             ],
             "description": "Symfony Finder Component",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T09:56:45+00:00"
         },
         {
@@ -6976,20 +6416,6 @@
                 "redlock",
                 "semaphore"
             ],
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-17T07:39:58+00:00"
         },
         {
@@ -7055,20 +6481,6 @@
             ],
             "description": "Symfony PHPUnit Bridge",
             "homepage": "https://symfony.com",
-            "funding": [
-                {
-                    "url": "https://symfony.com/sponsor",
-                    "type": "custom"
-                },
-                {
-                    "url": "https://github.com/fabpot",
-                    "type": "github"
-                },
-                {
-                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
-                    "type": "tidelift"
-                }
-            ],
             "time": "2020-08-28T16:19:35+00:00"
         },
         {
@@ -7109,12 +6521,6 @@
                 }
             ],
             "description": "A small library for converting tokenized PHP source code into XML and potentially other formats",
-            "funding": [
-                {
-                    "url": "https://github.com/theseer",
-                    "type": "github"
-                }
-            ],
             "time": "2020-07-12T23:59:07+00:00"
         },
         {
@@ -7167,16 +6573,23 @@
             "time": "2020-07-08T17:02:28+00:00"
         }
     ],
-    "aliases": [],
+    "aliases": [
+        {
+            "alias": "v1.3.4",
+            "alias_normalized": "1.3.4.0",
+            "version": "dev-SF5",
+            "package": "behat/mink-browserkit-driver"
+        }
+    ],
     "minimum-stability": "dev",
     "stability-flags": {
         "drupal/core": 20,
         "drupal/core-project-message": 20,
-        "drupal/core-vendor-hardening": 20
+        "drupal/core-vendor-hardening": 20,
+        "behat/mink-browserkit-driver": 20
     },
     "prefer-stable": true,
     "prefer-lowest": false,
     "platform": [],
-    "platform-dev": [],
-    "plugin-api-version": "1.1.0"
+    "platform-dev": []
 }
diff --git a/composer/Metapackage/CoreRecommended/composer.json b/composer/Metapackage/CoreRecommended/composer.json
index 39e3d9b6d0d..714094710f1 100644
--- a/composer/Metapackage/CoreRecommended/composer.json
+++ b/composer/Metapackage/CoreRecommended/composer.json
@@ -13,6 +13,8 @@
         "doctrine/annotations": "1.10.4",
         "doctrine/lexer": "1.2.1",
         "doctrine/reflection": "1.2.1",
+        "drupal/core-project-message": "9.1.x-dev",
+        "drupal/core-vendor-hardening": "9.1.x-dev",
         "egulias/email-validator": "2.1.19",
         "guzzlehttp/guzzle": "6.5.5",
         "guzzlehttp/promises": "v1.3.1",
diff --git a/composer/Metapackage/DevDependencies/composer.json b/composer/Metapackage/DevDependencies/composer.json
index 3c107300090..0bb6fccc0c1 100644
--- a/composer/Metapackage/DevDependencies/composer.json
+++ b/composer/Metapackage/DevDependencies/composer.json
@@ -8,6 +8,7 @@
     },
     "require": {
         "behat/mink": "^1.8",
+        "behat/mink-browserkit-driver": "dev-SF5 as v1.3.4",
         "behat/mink-goutte-driver": "^1.2",
         "behat/mink-selenium2-driver": "^1.4",
         "composer/composer": "^1.9.1",
@@ -17,13 +18,13 @@
         "mikey179/vfsstream": "^1.6.8",
         "phpspec/prophecy": "^1.7",
         "phpunit/phpunit": "^8.4.1",
-        "symfony/browser-kit": "^4.4",
-        "symfony/css-selector": "^4.4",
-        "symfony/dom-crawler": "^4.4 !=4.4.5",
-        "symfony/error-handler": "^4.4",
-        "symfony/filesystem": "^4.4",
-        "symfony/finder": "^4.4",
-        "symfony/lock": "^4.4",
+        "symfony/browser-kit": "^4.4|^5.1",
+        "symfony/css-selector": "^4.4|^5.1",
+        "symfony/dom-crawler": "^4.4|^5.1 !=4.4.5",
+        "symfony/error-handler": "^4.4|^5.1",
+        "symfony/filesystem": "^4.4|^5.1",
+        "symfony/finder": "^4.4|^5.1",
+        "symfony/lock": "^4.4|^5.1",
         "symfony/phpunit-bridge": "^5.1.4",
         "symfony/var-dumper": "^5.1.2"
     }
diff --git a/composer/Metapackage/PinnedDevDependencies/composer.json b/composer/Metapackage/PinnedDevDependencies/composer.json
index f032858e0a9..131336ef9cc 100644
--- a/composer/Metapackage/PinnedDevDependencies/composer.json
+++ b/composer/Metapackage/PinnedDevDependencies/composer.json
@@ -9,7 +9,7 @@
     "require": {
         "drupal/core": "9.1.x-dev",
         "behat/mink": "v1.8.1",
-        "behat/mink-browserkit-driver": "v1.3.4",
+        "behat/mink-browserkit-driver": "dev-SF5",
         "behat/mink-goutte-driver": "v1.2.1",
         "behat/mink-selenium2-driver": "v1.4.0",
         "composer/ca-bundle": "1.2.8",
diff --git a/core/composer.json b/core/composer.json
index cf64c7800f2..dc97cf799cc 100644
--- a/core/composer.json
+++ b/core/composer.json
@@ -18,18 +18,19 @@
         "ext-tokenizer": "*",
         "ext-xml": "*",
         "php": ">=7.3",
-        "symfony/console": "^4.4",
-        "symfony/dependency-injection": "^4.4",
-        "symfony/event-dispatcher": "^4.4",
-        "symfony/http-foundation": "^4.4.7",
-        "symfony/http-kernel": "^4.4",
-        "symfony/routing": "^4.4",
-        "symfony/serializer": "^4.4",
-        "symfony/translation": "^4.4",
-        "symfony/validator": "^4.4",
-        "symfony/process": "^4.4",
+        "symfony/console": "^4.4|^5.1",
+        "symfony/dependency-injection": "^4.4|^5.1",
+        "symfony/event-dispatcher": "^4.4|^5.1",
+        "symfony/http-foundation": "^4.4.7|^5.1",
+        "symfony/http-kernel": "^4.4|^5.1",
+        "symfony/mime": "^4.3|^5.1",
+        "symfony/routing": "^4.4|^5.1",
+        "symfony/serializer": "^4.4|^5.1",
+        "symfony/translation": "^4.4|^5.1",
+        "symfony/validator": "^4.4|^5.1",
+        "symfony/process": "^4.4|^5.1",
         "symfony/polyfill-iconv": "^1.0",
-        "symfony/yaml": "^4.4",
+        "symfony/yaml": "^4.4|^5.1",
         "typo3/phar-stream-wrapper": "^3.1.3",
         "twig/twig": "^2.12.0",
         "doctrine/reflection": "^1.1",
diff --git a/core/core.api.php b/core/core.api.php
index 999ee3d9737..5c8f8a1d453 100644
--- a/core/core.api.php
+++ b/core/core.api.php
@@ -2502,7 +2502,7 @@ function hook_validation_constraint_alter(array &$definitions) {
  *
  * @section sec_dispatch Dispatching events
  * To dispatch an event, call the
- * \Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch()
+ * \Symfony\Contracts\EventDispatcher\EventDispatcherInterface::dispatch()
  * method on the 'event_dispatcher' service (see the
  * @link container Services topic @endlink for more information about how to
  * interact with services). The first argument is the unique event name, which
diff --git a/core/drupalci.yml b/core/drupalci.yml
index 63df934307e..269c69e26b3 100644
--- a/core/drupalci.yml
+++ b/core/drupalci.yml
@@ -14,6 +14,8 @@ build:
         # phpcs will use core's specified version of Coder.
         sniff-all-files: false
         halt-on-fail: false
+      container_command:
+        commands: "cd ${SOURCE_DIR} && rm -rf vendor/drupal/coder && composer update -n"
     testing:
       # run_tests task is executed several times in order of performance speeds.
       # halt-on-fail can be set on the run_tests tasks in order to fail fast.
diff --git a/core/lib/Drupal/Component/DependencyInjection/composer.json b/core/lib/Drupal/Component/DependencyInjection/composer.json
index e370fa3ed78..c364aa687d0 100644
--- a/core/lib/Drupal/Component/DependencyInjection/composer.json
+++ b/core/lib/Drupal/Component/DependencyInjection/composer.json
@@ -12,7 +12,7 @@
   },
   "require": {
     "php": ">=7.3.0",
-    "symfony/dependency-injection": "^4.4",
+    "symfony/dependency-injection": "^4.4|^5.1",
     "symfony/service-contracts": "^1.1|^2"
   },
   "suggest": {
diff --git a/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php b/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php
index 0cf5669543c..3919c09d4f7 100644
--- a/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php
+++ b/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php
@@ -3,11 +3,9 @@
 namespace Drupal\Component\EventDispatcher;
 
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\Event;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
-use Symfony\Contracts\EventDispatcher\Event as ContractsEvent;
-use Symfony\Contracts\EventDispatcher\EventDispatcherInterface as ContractsEventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\Event;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * A performance optimized container aware event dispatcher.
@@ -88,40 +86,8 @@ public function __construct(ContainerInterface $container, array $listeners = []
   /**
    * {@inheritdoc}
    */
-  public function dispatch($event/*, string $event_name = NULL*/) {
-    $event_name = 1 < \func_num_args() ? func_get_arg(1) : NULL;
-    if (\is_object($event)) {
-      $class_name = get_class($event);
-      $event_name = $event_name ?? $class_name;
-
-      $deprecation_message = 'Symfony\Component\EventDispatcher\Event is deprecated in drupal:9.1.0 and will be replaced by Symfony\Contracts\EventDispatcher\Event in drupal:10.0.0. A new Drupal\Component\EventDispatcher\Event class is available to bridge the two versions of the class. See https://www.drupal.org/node/3159012';
-
-      // Trigger a deprecation error if the deprecated Event class is used
-      // directly.
-      if ($class_name === 'Symfony\Component\EventDispatcher\Event') {
-        @trigger_error($deprecation_message, E_USER_DEPRECATED);
-      }
-      // Also try to trigger deprecation errors when classes are in the Drupal
-      // namespace and inherit directly from the deprecated class. If a class is
-      // in the Symfony namespace or a different one, we have to assume those
-      // will be updated by the dependency itself. Exclude the Drupal Event
-      // bridge class as a special case, otherwise it's pointless.
-      elseif ($class_name !== 'Drupal\Component\EventDispatcher\Event' && strpos($class_name, 'Drupal') !== FALSE) {
-        if (get_parent_class($event) === 'Symfony\Component\EventDispatcher\Event') {
-          @trigger_error($deprecation_message, E_USER_DEPRECATED);
-        }
-      }
-    }
-    elseif (\is_string($event) && (NULL === $event_name || $event_name instanceof ContractsEvent || $event_name instanceof Event)) {
-      @trigger_error('Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407', E_USER_DEPRECATED);
-      $swap = $event;
-      $event = $event_name ?? new Event();
-      $event_name = $swap;
-    }
-    else {
-      throw new \TypeError(sprintf('Argument 1 passed to "%s::dispatch()" must be an object, %s given.', ContractsEventDispatcherInterface::class, \gettype($event)));
-    }
-
+  public function dispatch(object $event, string $event_name = NULL): object {
+    $event_name = is_string($event_name) ? $event_name : get_class($event);
     if (isset($this->listeners[$event_name])) {
       // Sort listeners if necessary.
       if (isset($this->unsorted[$event_name])) {
diff --git a/core/lib/Drupal/Component/EventDispatcher/Event.php b/core/lib/Drupal/Component/EventDispatcher/Event.php
index 5d6dfe017e3..4586c735889 100644
--- a/core/lib/Drupal/Component/EventDispatcher/Event.php
+++ b/core/lib/Drupal/Component/EventDispatcher/Event.php
@@ -2,7 +2,7 @@
 
 namespace Drupal\Component\EventDispatcher;
 
-use Symfony\Component\EventDispatcher\Event as SymfonyEvent;
+use Symfony\Contracts\EventDispatcher\Event as SymfonyEvent;
 
 /**
  * Provides a forward-compatibility layer for the Symfony 5 event class.
diff --git a/core/lib/Drupal/Component/EventDispatcher/composer.json b/core/lib/Drupal/Component/EventDispatcher/composer.json
index 3574908ffbd..3d19f9682ba 100644
--- a/core/lib/Drupal/Component/EventDispatcher/composer.json
+++ b/core/lib/Drupal/Component/EventDispatcher/composer.json
@@ -6,8 +6,8 @@
   "license": "GPL-2.0-or-later",
   "require": {
     "php": ">=7.3.0",
-    "symfony/dependency-injection": "^4.4",
-    "symfony/event-dispatcher": "^4.4",
+    "symfony/dependency-injection": "^4.4|^5.1",
+    "symfony/event-dispatcher": "^4.4|^5.1",
     "symfony/event-dispatcher-contracts": "^1.1"
   },
   "autoload": {
diff --git a/core/lib/Drupal/Component/HttpFoundation/composer.json b/core/lib/Drupal/Component/HttpFoundation/composer.json
index 0c481d6011f..8e27fffea95 100644
--- a/core/lib/Drupal/Component/HttpFoundation/composer.json
+++ b/core/lib/Drupal/Component/HttpFoundation/composer.json
@@ -6,7 +6,7 @@
   "license": "GPL-2.0-or-later",
   "require": {
     "php": ">=7.3.0",
-    "symfony/http-foundation": "^4.4"
+    "symfony/http-foundation": "^4.4|^5.1"
   },
   "autoload": {
     "psr-4": {
diff --git a/core/lib/Drupal/Component/Plugin/composer.json b/core/lib/Drupal/Component/Plugin/composer.json
index 8814a8ef3a9..388df7369b9 100644
--- a/core/lib/Drupal/Component/Plugin/composer.json
+++ b/core/lib/Drupal/Component/Plugin/composer.json
@@ -6,7 +6,7 @@
   "license": "GPL-2.0-or-later",
   "require": {
     "php": ">=7.3.0",
-    "symfony/validator": "^4.4"
+    "symfony/validator": "^4.4|^5.1"
   },
   "autoload": {
     "psr-4": {
diff --git a/core/lib/Drupal/Component/Serialization/composer.json b/core/lib/Drupal/Component/Serialization/composer.json
index 7b40c55ddc3..8c97ce4b608 100644
--- a/core/lib/Drupal/Component/Serialization/composer.json
+++ b/core/lib/Drupal/Component/Serialization/composer.json
@@ -6,7 +6,7 @@
   "license": "GPL-2.0-or-later",
   "require": {
     "php": ">=7.3.0",
-    "symfony/yaml": "^4.4"
+    "symfony/yaml": "^4.4|^5.1"
   },
   "autoload": {
     "psr-4": {
diff --git a/core/lib/Drupal/Core/Action/Plugin/Action/GotoAction.php b/core/lib/Drupal/Core/Action/Plugin/Action/GotoAction.php
index b19a3d991cd..9fb6b0b61e8 100644
--- a/core/lib/Drupal/Core/Action/Plugin/Action/GotoAction.php
+++ b/core/lib/Drupal/Core/Action/Plugin/Action/GotoAction.php
@@ -10,7 +10,7 @@
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Utility\UnroutedUrlAssemblerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpKernel\KernelEvents;
 
@@ -28,7 +28,7 @@ class GotoAction extends ConfigurableActionBase implements ContainerFactoryPlugi
   /**
    * The event dispatcher service.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $dispatcher;
 
@@ -48,7 +48,7 @@ class GotoAction extends ConfigurableActionBase implements ContainerFactoryPlugi
    *   The plugin ID for the plugin instance.
    * @param mixed $plugin_definition
    *   The plugin implementation definition.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $dispatcher
    *   The tempstore factory.
    * @param \Drupal\Core\Utility\UnroutedUrlAssemblerInterface $url_assembler
    *   The unrouted URL assembler service.
diff --git a/core/lib/Drupal/Core/Config/Config.php b/core/lib/Drupal/Core/Config/Config.php
index 026bb55e9fa..38bb3d5db77 100644
--- a/core/lib/Drupal/Core/Config/Config.php
+++ b/core/lib/Drupal/Core/Config/Config.php
@@ -4,7 +4,7 @@
 
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Cache\Cache;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines the default configuration object.
@@ -21,7 +21,7 @@ class Config extends StorableConfigBase {
   /**
    * An event dispatcher instance to use for configuration events.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -57,7 +57,7 @@ class Config extends StorableConfigBase {
    * @param \Drupal\Core\Config\StorageInterface $storage
    *   A storage object to use for reading and writing the
    *   configuration data.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   An event dispatcher instance to use for configuration events.
    * @param \Drupal\Core\Config\TypedConfigManagerInterface $typed_config
    *   The typed configuration manager service.
diff --git a/core/lib/Drupal/Core/Config/ConfigFactory.php b/core/lib/Drupal/Core/Config/ConfigFactory.php
index 53e04d2785b..112cd9f311a 100644
--- a/core/lib/Drupal/Core/Config/ConfigFactory.php
+++ b/core/lib/Drupal/Core/Config/ConfigFactory.php
@@ -4,7 +4,7 @@
 
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Cache\Cache;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
 /**
@@ -34,7 +34,7 @@ class ConfigFactory implements ConfigFactoryInterface, EventSubscriberInterface
   /**
    * An event dispatcher instance to use for configuration events.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -64,7 +64,7 @@ class ConfigFactory implements ConfigFactoryInterface, EventSubscriberInterface
    *
    * @param \Drupal\Core\Config\StorageInterface $storage
    *   The configuration storage engine.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   An event dispatcher instance to use for configuration events.
    * @param \Drupal\Core\Config\TypedConfigManagerInterface $typed_config
    *   The typed configuration manager.
diff --git a/core/lib/Drupal/Core/Config/ConfigImporter.php b/core/lib/Drupal/Core/Config/ConfigImporter.php
index 25b7d0afbbe..05e2ea21042 100644
--- a/core/lib/Drupal/Core/Config/ConfigImporter.php
+++ b/core/lib/Drupal/Core/Config/ConfigImporter.php
@@ -13,7 +13,7 @@
 use Drupal\Core\Lock\LockBackendInterface;
 use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\Core\StringTranslation\TranslationInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines a configuration importer.
@@ -53,7 +53,7 @@ class ConfigImporter {
   /**
    * The event dispatcher used to notify subscribers.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -172,7 +172,7 @@ class ConfigImporter {
    * @param \Drupal\Core\Config\StorageComparerInterface $storage_comparer
    *   A storage comparer object used to determine configuration changes and
    *   access the source and target storage objects.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher used to notify subscribers of config import events.
    * @param \Drupal\Core\Config\ConfigManagerInterface $config_manager
    *   The configuration manager.
diff --git a/core/lib/Drupal/Core/Config/ConfigInstaller.php b/core/lib/Drupal/Core/Config/ConfigInstaller.php
index 235a7c1a412..082de18d919 100644
--- a/core/lib/Drupal/Core/Config/ConfigInstaller.php
+++ b/core/lib/Drupal/Core/Config/ConfigInstaller.php
@@ -5,7 +5,7 @@
 use Drupal\Component\Utility\Crypt;
 use Drupal\Core\Config\Entity\ConfigDependencyManager;
 use Drupal\Core\Installer\InstallerKernel;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 class ConfigInstaller implements ConfigInstallerInterface {
 
@@ -40,7 +40,7 @@ class ConfigInstaller implements ConfigInstallerInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -76,7 +76,7 @@ class ConfigInstaller implements ConfigInstallerInterface {
    *   The typed configuration manager.
    * @param \Drupal\Core\Config\ConfigManagerInterface $config_manager
    *   The configuration manager.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param string $install_profile
    *   The name of the currently active installation profile.
diff --git a/core/lib/Drupal/Core/Config/ConfigManager.php b/core/lib/Drupal/Core/Config/ConfigManager.php
index 71549978f35..c6ea46f7589 100644
--- a/core/lib/Drupal/Core/Config/ConfigManager.php
+++ b/core/lib/Drupal/Core/Config/ConfigManager.php
@@ -12,7 +12,7 @@
 use Drupal\Core\Serialization\Yaml;
 use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\Core\StringTranslation\TranslationInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * The ConfigManager provides helper functions for the configuration system.
@@ -59,7 +59,7 @@ class ConfigManager implements ConfigManagerInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -90,7 +90,7 @@ class ConfigManager implements ConfigManagerInterface {
    *   The string translation service.
    * @param \Drupal\Core\Config\StorageInterface $active_storage
    *   The active configuration storage.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Entity\EntityRepositoryInterface $entity_repository
    *   The entity repository.
diff --git a/core/lib/Drupal/Core/Config/ExportStorageManager.php b/core/lib/Drupal/Core/Config/ExportStorageManager.php
index aeaadedeb54..43591717abd 100644
--- a/core/lib/Drupal/Core/Config/ExportStorageManager.php
+++ b/core/lib/Drupal/Core/Config/ExportStorageManager.php
@@ -4,7 +4,7 @@
 
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Lock\LockBackendInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * The export storage manager dispatches an event for the export storage.
@@ -39,7 +39,7 @@ final class ExportStorageManager implements StorageManagerInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -57,7 +57,7 @@ final class ExportStorageManager implements StorageManagerInterface {
    *   The active config storage to prime the export storage.
    * @param \Drupal\Core\Database\Connection $connection
    *   The database connection.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Lock\LockBackendInterface $lock
    *   The used lock backend instance.
diff --git a/core/lib/Drupal/Core/Config/ImportStorageTransformer.php b/core/lib/Drupal/Core/Config/ImportStorageTransformer.php
index fcd5a12d59b..13efb7507c7 100644
--- a/core/lib/Drupal/Core/Config/ImportStorageTransformer.php
+++ b/core/lib/Drupal/Core/Config/ImportStorageTransformer.php
@@ -4,7 +4,7 @@
 
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Lock\LockBackendInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * The import storage transformer helps to use the configuration management api.
@@ -26,7 +26,7 @@ final class ImportStorageTransformer {
   /**
    * The event dispatcher to get changes to the configuration.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -56,7 +56,7 @@ final class ImportStorageTransformer {
   /**
    * ImportStorageTransformer constructor.
    *
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Database\Connection $connection
    *   The database connection.
diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index a19197f4adf..14e0401dd10 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -595,9 +595,6 @@ public function preHandle(Request $request) {
     // Set the allowed protocols.
     UrlHelper::setAllowedProtocols($this->container->getParameter('filter_protocols'));
 
-    // Override of Symfony's MIME type guesser singleton.
-    MimeTypeGuesser::registerWithSymfonyGuesser($this->container);
-
     $this->prepared = TRUE;
   }
 
diff --git a/core/lib/Drupal/Core/Entity/EntityTypeListener.php b/core/lib/Drupal/Core/Entity/EntityTypeListener.php
index 32e7f477109..0768dee0c89 100644
--- a/core/lib/Drupal/Core/Entity/EntityTypeListener.php
+++ b/core/lib/Drupal/Core/Entity/EntityTypeListener.php
@@ -2,7 +2,7 @@
 
 namespace Drupal\Core\Entity;
 
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Reacts to entity type CRUD on behalf of the Entity system.
@@ -28,7 +28,7 @@ class EntityTypeListener implements EntityTypeListenerInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -46,7 +46,7 @@ class EntityTypeListener implements EntityTypeListenerInterface {
    *   The entity type manager.
    * @param \Drupal\Core\Entity\EntityFieldManagerInterface $entity_field_manager
    *   The entity field manager.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Entity\EntityLastInstalledSchemaRepositoryInterface $entity_last_installed_schema_repository
    *   The entity last installed schema repository.
diff --git a/core/lib/Drupal/Core/Field/FieldStorageDefinitionListener.php b/core/lib/Drupal/Core/Field/FieldStorageDefinitionListener.php
index 8e52ec66423..06e06488ab9 100644
--- a/core/lib/Drupal/Core/Field/FieldStorageDefinitionListener.php
+++ b/core/lib/Drupal/Core/Field/FieldStorageDefinitionListener.php
@@ -6,7 +6,7 @@
 use Drupal\Core\Entity\EntityFieldManagerInterface;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Entity\FieldableEntityStorageInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Reacts to field storage definition CRUD on behalf of the Entity system.
@@ -25,7 +25,7 @@ class FieldStorageDefinitionListener implements FieldStorageDefinitionListenerIn
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -55,7 +55,7 @@ class FieldStorageDefinitionListener implements FieldStorageDefinitionListenerIn
    *
    * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
    *   The entity type manager.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Entity\EntityLastInstalledSchemaRepositoryInterface $entity_last_installed_schema_repository
    *   The entity last installed schema repository.
diff --git a/core/lib/Drupal/Core/File/MimeType/ExtensionMimeTypeGuesser.php b/core/lib/Drupal/Core/File/MimeType/ExtensionMimeTypeGuesser.php
index b0798000aac..d7cf0c99b22 100644
--- a/core/lib/Drupal/Core/File/MimeType/ExtensionMimeTypeGuesser.php
+++ b/core/lib/Drupal/Core/File/MimeType/ExtensionMimeTypeGuesser.php
@@ -3,13 +3,12 @@
 namespace Drupal\Core\File\MimeType;
 
 use Drupal\Core\Extension\ModuleHandlerInterface;
-use Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface as LegacyMimeTypeGuesserInterface;
 use Symfony\Component\Mime\MimeTypeGuesserInterface;
 
 /**
  * Makes possible to guess the MIME type of a file using its extension.
  */
-class ExtensionMimeTypeGuesser implements MimeTypeGuesserInterface, LegacyMimeTypeGuesserInterface {
+class ExtensionMimeTypeGuesser implements MimeTypeGuesserInterface {
 
   /**
    * Default MIME extension mapping.
diff --git a/core/lib/Drupal/Core/Form/FormBuilder.php b/core/lib/Drupal/Core/Form/FormBuilder.php
index cc680fa9b96..1d92afc45d8 100644
--- a/core/lib/Drupal/Core/Form/FormBuilder.php
+++ b/core/lib/Drupal/Core/Form/FormBuilder.php
@@ -17,7 +17,7 @@
 use Drupal\Core\Render\ElementInfoManagerInterface;
 use Drupal\Core\Security\TrustedCallbackInterface;
 use Drupal\Core\Theme\ThemeManagerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpFoundation\FileBag;
 use Symfony\Component\HttpFoundation\ParameterBag;
 use Symfony\Component\HttpFoundation\RequestStack;
@@ -40,7 +40,7 @@ class FormBuilder implements FormBuilderInterface, FormValidatorInterface, FormS
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -157,7 +157,7 @@ class FormBuilder implements FormBuilderInterface, FormValidatorInterface, FormS
    *   The form cache.
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
    *   The request stack.
diff --git a/core/lib/Drupal/Core/ProxyClass/File/MimeType/ExtensionMimeTypeGuesser.php b/core/lib/Drupal/Core/ProxyClass/File/MimeType/ExtensionMimeTypeGuesser.php
index d3f3fef6ebb..f771e15b45a 100644
--- a/core/lib/Drupal/Core/ProxyClass/File/MimeType/ExtensionMimeTypeGuesser.php
+++ b/core/lib/Drupal/Core/ProxyClass/File/MimeType/ExtensionMimeTypeGuesser.php
@@ -12,7 +12,7 @@
      *
      * @see \Drupal\Component\ProxyBuilder
      */
-    class ExtensionMimeTypeGuesser implements \Symfony\Component\Mime\MimeTypeGuesserInterface, \Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface
+    class ExtensionMimeTypeGuesser implements \Symfony\Component\Mime\MimeTypeGuesserInterface
     {
 
         use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
diff --git a/core/lib/Drupal/Core/ProxyClass/File/MimeType/MimeTypeGuesser.php b/core/lib/Drupal/Core/ProxyClass/File/MimeType/MimeTypeGuesser.php
index bbc8b16e32e..94f6a7abe56 100644
--- a/core/lib/Drupal/Core/ProxyClass/File/MimeType/MimeTypeGuesser.php
+++ b/core/lib/Drupal/Core/ProxyClass/File/MimeType/MimeTypeGuesser.php
@@ -12,7 +12,7 @@
      *
      * @see \Drupal\Component\ProxyBuilder
      */
-    class MimeTypeGuesser implements \Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface, \Symfony\Component\Mime\MimeTypeGuesserInterface
+    class MimeTypeGuesser implements \Symfony\Component\Mime\MimeTypeGuesserInterface
     {
 
         use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
@@ -86,19 +86,11 @@ public function guess($path)
         /**
          * {@inheritdoc}
          */
-        public function addMimeTypeGuesser($guesser, $priority = 0)
+        public function addMimeTypeGuesser(\Symfony\Component\Mime\MimeTypeGuesserInterface $guesser, $priority = 0)
         {
             return $this->lazyLoadItself()->addMimeTypeGuesser($guesser, $priority);
         }
 
-        /**
-         * {@inheritdoc}
-         */
-        public function addGuesser(\Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface $guesser, $priority = 0)
-        {
-            return $this->lazyLoadItself()->addGuesser($guesser, $priority);
-        }
-
         /**
          * {@inheritdoc}
          */
diff --git a/core/lib/Drupal/Core/Render/HtmlResponse.php b/core/lib/Drupal/Core/Render/HtmlResponse.php
index 763696d109d..75b8b29ae3a 100644
--- a/core/lib/Drupal/Core/Render/HtmlResponse.php
+++ b/core/lib/Drupal/Core/Render/HtmlResponse.php
@@ -24,10 +24,27 @@ class HtmlResponse extends Response implements CacheableResponseInterface, Attac
   use CacheableResponseTrait;
   use AttachmentsTrait;
 
+  public function __construct(
+    ?string $content = '',
+    int $status = 200,
+    array $headers = []
+  ) {
+    parent::__construct($this->getMarkup($content), $status, $headers);
+  }
+
   /**
    * {@inheritdoc}
    */
   public function setContent($content) {
+    return parent::setContent($this->getMarkup($content));
+  }
+
+  /**
+   * @param mixed $content
+   *
+   * @return array[]|mixed|string
+   */
+  protected function getMarkup($content = '') {
     // A render array can automatically be converted to a string and set the
     // necessary metadata.
     if (is_array($content) && (isset($content['#markup']))) {
@@ -41,8 +58,7 @@ public function setContent($content) {
       $this->setAttachments($content['#attached']);
       $content = $content['#markup'];
     }
-
-    return parent::setContent($content);
+    return $content;
   }
 
 }
diff --git a/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php b/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
index 66af0a82d40..46992d8f68c 100644
--- a/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
+++ b/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
@@ -16,7 +16,7 @@
 use Drupal\Core\Render\RenderEvents;
 use Drupal\Core\Routing\RouteMatchInterface;
 use Drupal\Core\Theme\ThemeManagerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpFoundation\Request;
 
 /**
@@ -48,7 +48,7 @@ class HtmlRenderer implements MainContentRendererInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
   /**
@@ -95,7 +95,7 @@ class HtmlRenderer implements MainContentRendererInterface {
    *   The title resolver.
    * @param \Drupal\Component\Plugin\PluginManagerInterface $display_variant_manager
    *   The display variant manager.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler.
diff --git a/core/lib/Drupal/Core/Routing/RouteBuilder.php b/core/lib/Drupal/Core/Routing/RouteBuilder.php
index b0f785fd9f4..43dd1569b01 100644
--- a/core/lib/Drupal/Core/Routing/RouteBuilder.php
+++ b/core/lib/Drupal/Core/Routing/RouteBuilder.php
@@ -9,7 +9,7 @@
 use Drupal\Core\Lock\LockBackendInterface;
 use Drupal\Core\DestructableInterface;
 use Drupal\Component\EventDispatcher\Event;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\Routing\RouteCollection;
 use Symfony\Component\Routing\Route;
 
@@ -35,7 +35,7 @@ class RouteBuilder implements RouteBuilderInterface, DestructableInterface {
   /**
    * The event dispatcher to notify of routes.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $dispatcher;
 
@@ -88,7 +88,7 @@ class RouteBuilder implements RouteBuilderInterface, DestructableInterface {
    *   The matcher dumper used to store the route information.
    * @param \Drupal\Core\Lock\LockBackendInterface $lock
    *   The lock backend.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $dispatcher
    *   The event dispatcher to notify of routes.
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler.
diff --git a/core/lib/Drupal/Core/Session/AccountProxy.php b/core/lib/Drupal/Core/Session/AccountProxy.php
index 2815c631526..72746887063 100644
--- a/core/lib/Drupal/Core/Session/AccountProxy.php
+++ b/core/lib/Drupal/Core/Session/AccountProxy.php
@@ -3,7 +3,7 @@
 namespace Drupal\Core\Session;
 
 use Drupal\Core\DependencyInjection\DependencySerializationTrait;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * A proxied implementation of AccountInterface.
@@ -37,14 +37,14 @@ class AccountProxy implements AccountProxyInterface {
   /**
    * Event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
   /**
    * AccountProxy constructor.
    *
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $eventDispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $eventDispatcher
    *   Event dispatcher.
    */
   public function __construct(EventDispatcherInterface $eventDispatcher) {
diff --git a/core/modules/big_pipe/src/Render/BigPipe.php b/core/modules/big_pipe/src/Render/BigPipe.php
index f21640bc4e5..38fec0d9387 100644
--- a/core/modules/big_pipe/src/Render/BigPipe.php
+++ b/core/modules/big_pipe/src/Render/BigPipe.php
@@ -11,7 +11,7 @@
 use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Render\HtmlResponse;
 use Drupal\Core\Render\RendererInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\RequestStack;
 use Symfony\Component\HttpFoundation\Response;
@@ -194,7 +194,7 @@ class BigPipe {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -216,7 +216,7 @@ class BigPipe {
    *   The request stack.
    * @param \Symfony\Component\HttpKernel\HttpKernelInterface $http_kernel
    *   The HTTP kernel.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
diff --git a/core/modules/big_pipe/tests/src/Unit/Render/ManyPlaceholderTest.php b/core/modules/big_pipe/tests/src/Unit/Render/ManyPlaceholderTest.php
index fb835e4ce51..28eab58754c 100644
--- a/core/modules/big_pipe/tests/src/Unit/Render/ManyPlaceholderTest.php
+++ b/core/modules/big_pipe/tests/src/Unit/Render/ManyPlaceholderTest.php
@@ -8,7 +8,7 @@
 use Drupal\Core\Render\HtmlResponse;
 use Drupal\Core\Render\RendererInterface;
 use Drupal\Tests\UnitTestCase;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpFoundation\RequestStack;
 use Symfony\Component\HttpFoundation\Session\SessionInterface;
 use Symfony\Component\HttpKernel\HttpKernelInterface;
diff --git a/core/modules/block_content/src/BlockContentAccessControlHandler.php b/core/modules/block_content/src/BlockContentAccessControlHandler.php
index 0c84190997f..5ea6cfce1f6 100644
--- a/core/modules/block_content/src/BlockContentAccessControlHandler.php
+++ b/core/modules/block_content/src/BlockContentAccessControlHandler.php
@@ -11,7 +11,7 @@
 use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Core\Session\AccountInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines the access control handler for the custom block entity type.
@@ -23,7 +23,7 @@ class BlockContentAccessControlHandler extends EntityAccessControlHandler implem
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -32,7 +32,7 @@ class BlockContentAccessControlHandler extends EntityAccessControlHandler implem
    *
    * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
    *   The entity type.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $dispatcher
    *   The event dispatcher.
    */
   public function __construct(EntityTypeInterface $entity_type, EventDispatcherInterface $dispatcher) {
diff --git a/core/modules/config/src/Form/ConfigSingleImportForm.php b/core/modules/config/src/Form/ConfigSingleImportForm.php
index f4236b5e3b9..bf6d650d5f6 100644
--- a/core/modules/config/src/Form/ConfigSingleImportForm.php
+++ b/core/modules/config/src/Form/ConfigSingleImportForm.php
@@ -24,7 +24,7 @@
 use Drupal\Core\Serialization\Yaml;
 use Drupal\Core\Url;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Provides a form for importing a single configuration file.
@@ -57,7 +57,7 @@ class ConfigSingleImportForm extends ConfirmFormBase {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -133,7 +133,7 @@ class ConfigSingleImportForm extends ConfirmFormBase {
    *   The config storage.
    * @param \Drupal\Core\Render\RendererInterface $renderer
    *   The renderer service.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher used to notify subscribers of config import events.
    * @param \Drupal\Core\Config\ConfigManagerInterface $config_manager
    *   The configuration manager.
diff --git a/core/modules/config/src/Form/ConfigSync.php b/core/modules/config/src/Form/ConfigSync.php
index 70a849c20fd..47af171368f 100644
--- a/core/modules/config/src/Form/ConfigSync.php
+++ b/core/modules/config/src/Form/ConfigSync.php
@@ -19,7 +19,7 @@
 use Drupal\Core\Config\StorageComparer;
 use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Url;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -60,7 +60,7 @@ class ConfigSync extends FormBase {
   /**
    * Event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -131,7 +131,7 @@ class ConfigSync extends FormBase {
    *   The snapshot storage.
    * @param \Drupal\Core\Lock\LockBackendInterface $lock
    *   The lock object.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   Event dispatcher.
    * @param \Drupal\Core\Config\ConfigManagerInterface $config_manager
    *   Configuration manager.
diff --git a/core/modules/config_translation/src/ConfigEntityMapper.php b/core/modules/config_translation/src/ConfigEntityMapper.php
index 9471a629491..cbc716baf2f 100644
--- a/core/modules/config_translation/src/ConfigEntityMapper.php
+++ b/core/modules/config_translation/src/ConfigEntityMapper.php
@@ -13,7 +13,7 @@
 use Drupal\Core\Url;
 use Drupal\locale\LocaleConfigManager;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -74,7 +74,7 @@ class ConfigEntityMapper extends ConfigNamesMapper {
    *   The entity type manager.
    * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
    *   The language manager.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    */
   public function __construct($plugin_id, $plugin_definition, ConfigFactoryInterface $config_factory, TypedConfigManagerInterface $typed_config, LocaleConfigManager $locale_config_manager, ConfigMapperManagerInterface $config_mapper_manager, RouteProviderInterface $route_provider, TranslationInterface $translation_manager, EntityTypeManagerInterface $entity_type_manager, LanguageManagerInterface $language_manager, EventDispatcherInterface $event_dispatcher = NULL) {
diff --git a/core/modules/config_translation/src/ConfigNamesMapper.php b/core/modules/config_translation/src/ConfigNamesMapper.php
index 188fd6fc672..a0068ceec83 100644
--- a/core/modules/config_translation/src/ConfigNamesMapper.php
+++ b/core/modules/config_translation/src/ConfigNamesMapper.php
@@ -17,7 +17,7 @@
 use Drupal\Core\Url;
 use Drupal\locale\LocaleConfigManager;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\Routing\Route;
 use Symfony\Component\Routing\RouteCollection;
 
@@ -92,7 +92,7 @@ class ConfigNamesMapper extends PluginBase implements ConfigMapperInterface, Con
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -125,7 +125,7 @@ class ConfigNamesMapper extends PluginBase implements ConfigMapperInterface, Con
    *   The string translation manager.
    * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
    *   The language manager.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   (optional) The event dispatcher.
    *
    * @throws \Symfony\Component\Routing\Exception\RouteNotFoundException
diff --git a/core/modules/config_translation/tests/src/Unit/ConfigEntityMapperTest.php b/core/modules/config_translation/tests/src/Unit/ConfigEntityMapperTest.php
index 6dc7abdc6d3..2e8260bdde6 100644
--- a/core/modules/config_translation/tests/src/Unit/ConfigEntityMapperTest.php
+++ b/core/modules/config_translation/tests/src/Unit/ConfigEntityMapperTest.php
@@ -52,7 +52,7 @@ class ConfigEntityMapperTest extends UnitTestCase {
   /**
    * The mocked event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -86,7 +86,7 @@ protected function setUp(): void {
 
     $this->languageManager = $this->createMock('Drupal\Core\Language\LanguageManagerInterface');
 
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
 
     $this->configEntityMapper = new ConfigEntityMapper(
       'configurable_language',
diff --git a/core/modules/config_translation/tests/src/Unit/ConfigFieldMapperTest.php b/core/modules/config_translation/tests/src/Unit/ConfigFieldMapperTest.php
index 3c45cf08009..e1f9b16ecdb 100644
--- a/core/modules/config_translation/tests/src/Unit/ConfigFieldMapperTest.php
+++ b/core/modules/config_translation/tests/src/Unit/ConfigFieldMapperTest.php
@@ -38,7 +38,7 @@ class ConfigFieldMapperTest extends UnitTestCase {
   /**
    * The mocked event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -61,7 +61,7 @@ protected function setUp(): void {
       ->disableOriginalConstructor()
       ->getMock();
 
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
 
     $this->configFieldMapper = new ConfigFieldMapper(
       'node_fields',
diff --git a/core/modules/config_translation/tests/src/Unit/ConfigNamesMapperTest.php b/core/modules/config_translation/tests/src/Unit/ConfigNamesMapperTest.php
index 51697f01a25..b50419d4182 100644
--- a/core/modules/config_translation/tests/src/Unit/ConfigNamesMapperTest.php
+++ b/core/modules/config_translation/tests/src/Unit/ConfigNamesMapperTest.php
@@ -91,7 +91,7 @@ class ConfigNamesMapperTest extends UnitTestCase {
   /**
    * The mocked event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -129,7 +129,7 @@ protected function setUp(): void {
 
     $this->languageManager = $this->createMock('Drupal\Core\Language\LanguageManagerInterface');
 
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
 
     $this->configNamesMapper = new TestConfigNamesMapper(
       'system.site_information_settings',
diff --git a/core/modules/jsonapi/src/ResourceType/ResourceTypeRepository.php b/core/modules/jsonapi/src/ResourceType/ResourceTypeRepository.php
index c2d306d4b9f..8a80c36f02b 100644
--- a/core/modules/jsonapi/src/ResourceType/ResourceTypeRepository.php
+++ b/core/modules/jsonapi/src/ResourceType/ResourceTypeRepository.php
@@ -15,7 +15,7 @@
 use Drupal\Core\Entity\FieldableEntityInterface;
 use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\TypedData\DataReferenceTargetDefinition;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpKernel\Exception\PreconditionFailedHttpException;
 
 /**
@@ -71,7 +71,7 @@ class ResourceTypeRepository implements ResourceTypeRepositoryInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -101,7 +101,7 @@ class ResourceTypeRepository implements ResourceTypeRepositoryInterface {
    *   The entity field manager.
    * @param \Drupal\Core\Cache\CacheBackendInterface $cache
    *   The cache backend.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $dispatcher
    *   The event dispatcher.
    */
   public function __construct(EntityTypeManagerInterface $entity_type_manager, EntityTypeBundleInfoInterface $entity_bundle_info, EntityFieldManagerInterface $entity_field_manager, CacheBackendInterface $cache, EventDispatcherInterface $dispatcher) {
diff --git a/core/modules/language/src/Config/LanguageConfigFactoryOverride.php b/core/modules/language/src/Config/LanguageConfigFactoryOverride.php
index 3c7010d0345..67ae7dfa994 100644
--- a/core/modules/language/src/Config/LanguageConfigFactoryOverride.php
+++ b/core/modules/language/src/Config/LanguageConfigFactoryOverride.php
@@ -11,7 +11,7 @@
 use Drupal\Core\Config\TypedConfigManagerInterface;
 use Drupal\Core\Language\LanguageDefault;
 use Drupal\Core\Language\LanguageInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
 /**
@@ -48,7 +48,7 @@ class LanguageConfigFactoryOverride extends ConfigFactoryOverrideBase implements
   /**
    * An event dispatcher instance to use for configuration events.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -64,7 +64,7 @@ class LanguageConfigFactoryOverride extends ConfigFactoryOverrideBase implements
    *
    * @param \Drupal\Core\Config\StorageInterface $storage
    *   The configuration storage engine.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   An event dispatcher instance to use for configuration events.
    * @param \Drupal\Core\Config\TypedConfigManagerInterface $typed_config
    *   The typed configuration manager.
diff --git a/core/modules/language/src/Config/LanguageConfigOverride.php b/core/modules/language/src/Config/LanguageConfigOverride.php
index 01cd56c7e61..3b3b4da3c67 100644
--- a/core/modules/language/src/Config/LanguageConfigOverride.php
+++ b/core/modules/language/src/Config/LanguageConfigOverride.php
@@ -6,7 +6,7 @@
 use Drupal\Core\Config\StorableConfigBase;
 use Drupal\Core\Config\StorageInterface;
 use Drupal\Core\Config\TypedConfigManagerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines language configuration overrides.
@@ -18,7 +18,7 @@ class LanguageConfigOverride extends StorableConfigBase {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -32,7 +32,7 @@ class LanguageConfigOverride extends StorableConfigBase {
    *   configuration override.
    * @param \Drupal\Core\Config\TypedConfigManagerInterface $typed_config
    *   The typed configuration manager service.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    */
   public function __construct($name, StorageInterface $storage, TypedConfigManagerInterface $typed_config, EventDispatcherInterface $event_dispatcher) {
diff --git a/core/modules/language/tests/src/Unit/Config/LanguageConfigOverrideTest.php b/core/modules/language/tests/src/Unit/Config/LanguageConfigOverrideTest.php
index fac22730afd..2f789cdc8f6 100644
--- a/core/modules/language/tests/src/Unit/Config/LanguageConfigOverrideTest.php
+++ b/core/modules/language/tests/src/Unit/Config/LanguageConfigOverrideTest.php
@@ -30,7 +30,7 @@ class LanguageConfigOverrideTest extends UnitTestCase {
   /**
    * Event Dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -53,7 +53,7 @@ class LanguageConfigOverrideTest extends UnitTestCase {
    */
   protected function setUp(): void {
     $this->storage = $this->createMock('Drupal\Core\Config\StorageInterface');
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $this->typedConfig = $this->createMock('\Drupal\Core\Config\TypedConfigManagerInterface');
     $this->configTranslation = new LanguageConfigOverride('config.test', $this->storage, $this->typedConfig, $this->eventDispatcher);
     $this->cacheTagsInvalidator = $this->createMock('Drupal\Core\Cache\CacheTagsInvalidatorInterface');
diff --git a/core/modules/layout_builder/src/Element/LayoutBuilder.php b/core/modules/layout_builder/src/Element/LayoutBuilder.php
index 0814604bbcf..ad737d2e64c 100644
--- a/core/modules/layout_builder/src/Element/LayoutBuilder.php
+++ b/core/modules/layout_builder/src/Element/LayoutBuilder.php
@@ -14,7 +14,7 @@
 use Drupal\layout_builder\LayoutBuilderHighlightTrait;
 use Drupal\layout_builder\SectionStorageInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines a render element for building the Layout Builder UI.
@@ -33,7 +33,7 @@ class LayoutBuilder extends RenderElement implements ContainerFactoryPluginInter
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -46,7 +46,7 @@ class LayoutBuilder extends RenderElement implements ContainerFactoryPluginInter
    *   The plugin ID for the plugin instance.
    * @param mixed $plugin_definition
    *   The plugin implementation definition.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher service.
    * @param \Drupal\Core\Messenger\MessengerInterface|null $messenger
    *   The messenger service. This is no longer used and will be removed in
diff --git a/core/modules/layout_builder/src/SectionComponent.php b/core/modules/layout_builder/src/SectionComponent.php
index c09492e3ab5..b14fc6ae3d5 100644
--- a/core/modules/layout_builder/src/SectionComponent.php
+++ b/core/modules/layout_builder/src/SectionComponent.php
@@ -272,7 +272,7 @@ protected function contextHandler() {
   /**
    * Wraps the event dispatcher.
    *
-   * @return \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @return \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    *   The event dispatcher.
    */
   protected function eventDispatcher() {
diff --git a/core/modules/layout_builder/tests/src/Kernel/LayoutBuilderElementTest.php b/core/modules/layout_builder/tests/src/Kernel/LayoutBuilderElementTest.php
index 5748a99c43d..a7672ffec8a 100644
--- a/core/modules/layout_builder/tests/src/Kernel/LayoutBuilderElementTest.php
+++ b/core/modules/layout_builder/tests/src/Kernel/LayoutBuilderElementTest.php
@@ -6,7 +6,7 @@
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\layout_builder\Element\LayoutBuilder;
 use Drupal\layout_builder\LayoutTempstoreRepositoryInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Tests the deprecation notices of the layout builder element.
diff --git a/core/modules/layout_builder/tests/src/Unit/SectionComponentTest.php b/core/modules/layout_builder/tests/src/Unit/SectionComponentTest.php
index ca2138ec9ee..07364d9ad92 100644
--- a/core/modules/layout_builder/tests/src/Unit/SectionComponentTest.php
+++ b/core/modules/layout_builder/tests/src/Unit/SectionComponentTest.php
@@ -12,7 +12,7 @@
 use Drupal\layout_builder\SectionComponent;
 use Drupal\Tests\UnitTestCase;
 use Prophecy\Argument;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * @coversDefaultClass \Drupal\layout_builder\SectionComponent
diff --git a/core/modules/migrate/src/MigrateExecutable.php b/core/modules/migrate/src/MigrateExecutable.php
index 4f75c9486e5..a2f29ed7249 100644
--- a/core/modules/migrate/src/MigrateExecutable.php
+++ b/core/modules/migrate/src/MigrateExecutable.php
@@ -14,7 +14,7 @@
 use Drupal\migrate\Exception\RequirementsException;
 use Drupal\migrate\Plugin\MigrateIdMapInterface;
 use Drupal\migrate\Plugin\MigrationInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines a migrate executable class.
@@ -77,7 +77,7 @@ class MigrateExecutable implements MigrateExecutableInterface {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -97,7 +97,7 @@ class MigrateExecutable implements MigrateExecutableInterface {
    *   The migration to run.
    * @param \Drupal\migrate\MigrateMessageInterface $message
    *   (optional) The migrate message service.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   (optional) The event dispatcher.
    *
    * @throws \Drupal\migrate\MigrateException
@@ -135,7 +135,7 @@ protected function getSource() {
   /**
    * Gets the event dispatcher.
    *
-   * @return \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @return \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected function getEventDispatcher() {
     if (!$this->eventDispatcher) {
diff --git a/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
index 6675ec8947f..93e3f01b3b3 100644
--- a/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
+++ b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
@@ -19,7 +19,7 @@
 use Drupal\migrate\Event\MigrateMapSaveEvent;
 use Drupal\migrate\Event\MigrateMapDeleteEvent;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines the sql based ID map implementation.
@@ -39,7 +39,7 @@ class Sql extends PluginBase implements MigrateIdMapInterface, ContainerFactoryP
   /**
    * An event dispatcher instance to use for map events.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -154,7 +154,7 @@ class Sql extends PluginBase implements MigrateIdMapInterface, ContainerFactoryP
    *   The configuration for the plugin.
    * @param \Drupal\migrate\Plugin\MigrationInterface $migration
    *   The migration to do.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher.
    */
   public function __construct(array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration, EventDispatcherInterface $event_dispatcher) {
diff --git a/core/modules/migrate/tests/src/Unit/MigrateExecutableTest.php b/core/modules/migrate/tests/src/Unit/MigrateExecutableTest.php
index 68bf7d02d62..8673eaee644 100644
--- a/core/modules/migrate/tests/src/Unit/MigrateExecutableTest.php
+++ b/core/modules/migrate/tests/src/Unit/MigrateExecutableTest.php
@@ -52,7 +52,7 @@ protected function setUp(): void {
     parent::setUp();
     $this->migration = $this->getMigration();
     $this->message = $this->createMock('Drupal\migrate\MigrateMessageInterface');
-    $event_dispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $event_dispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $this->executable = new TestMigrateExecutable($this->migration, $this->message, $event_dispatcher);
     $this->executable->setStringTranslation($this->getStringTranslationStub());
   }
diff --git a/core/modules/migrate/tests/src/Unit/MigrateSourceTest.php b/core/modules/migrate/tests/src/Unit/MigrateSourceTest.php
index 466786cfcc2..b923d1fea6b 100644
--- a/core/modules/migrate/tests/src/Unit/MigrateSourceTest.php
+++ b/core/modules/migrate/tests/src/Unit/MigrateSourceTest.php
@@ -444,8 +444,8 @@ public function testDefaultPropertiesValues() {
   protected function getMigrateExecutable($migration) {
     /** @var \Drupal\migrate\MigrateMessageInterface $message */
     $message = $this->createMock('Drupal\migrate\MigrateMessageInterface');
-    /** @var \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher */
-    $event_dispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    /** @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher */
+    $event_dispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     return new MigrateExecutable($migration, $message, $event_dispatcher);
   }
 
diff --git a/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapEnsureTablesTest.php b/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapEnsureTablesTest.php
index 44eeccb7c17..e674ef4df71 100644
--- a/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapEnsureTablesTest.php
+++ b/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapEnsureTablesTest.php
@@ -230,8 +230,8 @@ protected function runEnsureTablesTest($schema) {
     $migration->expects($this->any())
       ->method('getDestinationPlugin')
       ->willReturn($plugin);
-    /** @var \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher */
-    $event_dispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    /** @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher */
+    $event_dispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $map = new TestSqlIdMap($database, [], 'sql', [], $migration, $event_dispatcher);
     $map->getDatabase();
   }
diff --git a/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php b/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php
index cd27e105975..4d598d05d06 100644
--- a/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php
+++ b/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php
@@ -110,7 +110,7 @@ protected function getIdMap() {
     $migration
       ->method('getDestinationPlugin')
       ->willReturn($plugin);
-    $event_dispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $event_dispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
 
     $id_map = new TestSqlIdMap($this->database, [], 'sql', [], $migration, $event_dispatcher);
     $migration
diff --git a/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php b/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
index 1adc95522f1..78bdb9e7c38 100644
--- a/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
+++ b/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
@@ -6,7 +6,7 @@
 use Drupal\migrate\Plugin\MigrationInterface;
 use Drupal\migrate\MigrateException;
 use Drupal\migrate\Plugin\migrate\id_map\Sql;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines a SQL ID map for use in tests.
@@ -26,7 +26,7 @@ class TestSqlIdMap extends Sql implements \Iterator {
    *   The configuration for the plugin.
    * @param \Drupal\migrate\Plugin\MigrationInterface $migration
    *   The migration to do.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher service.
    */
   public function __construct(Connection $database, array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration, EventDispatcherInterface $event_dispatcher) {
diff --git a/core/modules/migrate/tests/src/Unit/process/SubProcessTest.php b/core/modules/migrate/tests/src/Unit/process/SubProcessTest.php
index c7edcbecfb2..9563e78e2cb 100644
--- a/core/modules/migrate/tests/src/Unit/process/SubProcessTest.php
+++ b/core/modules/migrate/tests/src/Unit/process/SubProcessTest.php
@@ -8,7 +8,7 @@
 use Drupal\migrate\Plugin\migrate\process\SubProcess;
 use Drupal\migrate\Row;
 use Drupal\Tests\migrate\Unit\MigrateTestCase;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Tests the sub_process process plugin.
diff --git a/core/modules/user/src/UserFloodControl.php b/core/modules/user/src/UserFloodControl.php
index c5f79b7bf72..08c0f3a141b 100644
--- a/core/modules/user/src/UserFloodControl.php
+++ b/core/modules/user/src/UserFloodControl.php
@@ -5,7 +5,7 @@
 use Drupal\user\Event\UserEvents;
 use Drupal\user\Event\UserFloodEvent;
 use Drupal\Core\Flood\FloodInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpFoundation\RequestStack;
 
 /**
@@ -25,7 +25,7 @@ class UserFloodControl implements UserFloodControlInterface {
   /**
    * Event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
@@ -41,7 +41,7 @@ class UserFloodControl implements UserFloodControlInterface {
    *
    * @param \Drupal\Core\Flood\FloodInterface $flood
    *   The flood service.
-   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   The event dispatcher service.
    * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
    *   The request stack used to retrieve the current request.
diff --git a/core/modules/views/tests/src/Kernel/EventSubscriber/ViewsEntitySchemaSubscriberIntegrationTest.php b/core/modules/views/tests/src/Kernel/EventSubscriber/ViewsEntitySchemaSubscriberIntegrationTest.php
index fec962da588..abf27f20553 100644
--- a/core/modules/views/tests/src/Kernel/EventSubscriber/ViewsEntitySchemaSubscriberIntegrationTest.php
+++ b/core/modules/views/tests/src/Kernel/EventSubscriber/ViewsEntitySchemaSubscriberIntegrationTest.php
@@ -43,7 +43,7 @@ class ViewsEntitySchemaSubscriberIntegrationTest extends ViewsKernelTestBase {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface
    */
   protected $eventDispatcher;
 
diff --git a/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php b/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php
index 31fb5a5f8fd..89f8f6e8673 100644
--- a/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php
+++ b/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php
@@ -8,7 +8,6 @@
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
-use Symfony\Component\EventDispatcher\Event as SymfonyEvent;
 use Symfony\Component\EventDispatcher\GenericEvent;
 use Drupal\Component\EventDispatcher\Event;
 
@@ -142,30 +141,6 @@ public function testGetListenersWithServices() {
     $this->assertSame($expectedListeners, $actualListeners);
   }
 
-  /**
-   * Tests argument order deprecation.
-   *
-   * @group legacy
-   * @expectedDeprecation Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407
-   */
-  public function testDispatchArgumentOrderDeprecation() {
-    $container = new ContainerBuilder();
-    $dispatcher = new ContainerAwareEventDispatcher($container, []);
-    $dispatcher->dispatch('foo');
-  }
-
-  /**
-   * Tests deprecation notice for Symfony Event class.
-   *
-   * @group legacy
-   * @expectedDeprecation Symfony\Component\EventDispatcher\Event is deprecated in drupal:9.1.0 and will be replaced by Symfony\Contracts\EventDispatcher\Event in drupal:10.0.0. A new Drupal\Component\EventDispatcher\Event class is available to bridge the two versions of the class. See https://www.drupal.org/node/3159012
-   */
-  public function testSymfonyEventDeprecation() {
-    $container = new ContainerBuilder();
-    $dispatcher = new ContainerAwareEventDispatcher($container, []);
-    $dispatcher->dispatch(new SymfonyEvent());
-  }
-
   /**
    * Tests dispatching Symfony events with core's event dispatcher.
    */
@@ -175,18 +150,6 @@ public function testSymfonyEventDispatching() {
     $dispatcher->dispatch(new GenericEvent());
   }
 
-  /**
-   * Tests deprecation notice for Symfony Event class inheritance.
-   *
-   * @group legacy
-   * @expectedDeprecation Symfony\Component\EventDispatcher\Event is deprecated in drupal:9.1.0 and will be replaced by Symfony\Contracts\EventDispatcher\Event in drupal:10.0.0. A new Drupal\Component\EventDispatcher\Event class is available to bridge the two versions of the class. See https://www.drupal.org/node/3159012
-   */
-  public function testSymfonyInheritedEventDeprecation() {
-    $container = new ContainerBuilder();
-    $dispatcher = new ContainerAwareEventDispatcher($container, []);
-    $dispatcher->dispatch(new SymfonyInheritedEvent());
-  }
-
   public function testDispatchWithServices() {
     $container = new ContainerBuilder();
     $container->register('listener_service', TestEventListener::class);
@@ -647,5 +610,3 @@ public static function getSubscribedEvents() {
   }
 
 }
-
-class SymfonyInheritedEvent extends SymfonyEvent {}
diff --git a/core/tests/Drupal/Tests/Core/Config/ConfigFactoryTest.php b/core/tests/Drupal/Tests/Core/Config/ConfigFactoryTest.php
index c072052c7e2..21db97bb168 100644
--- a/core/tests/Drupal/Tests/Core/Config/ConfigFactoryTest.php
+++ b/core/tests/Drupal/Tests/Core/Config/ConfigFactoryTest.php
@@ -30,7 +30,7 @@ class ConfigFactoryTest extends UnitTestCase {
   /**
    * Event Dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -53,7 +53,7 @@ class ConfigFactoryTest extends UnitTestCase {
    */
   protected function setUp(): void {
     $this->storage = $this->createMock('Drupal\Core\Config\StorageInterface');
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $this->typedConfig = $this->createMock('\Drupal\Core\Config\TypedConfigManagerInterface');
     $this->configFactory = new ConfigFactory($this->storage, $this->eventDispatcher, $this->typedConfig);
 
diff --git a/core/tests/Drupal/Tests/Core/Config/ConfigTest.php b/core/tests/Drupal/Tests/Core/Config/ConfigTest.php
index ac09beb7a67..40c43525852 100644
--- a/core/tests/Drupal/Tests/Core/Config/ConfigTest.php
+++ b/core/tests/Drupal/Tests/Core/Config/ConfigTest.php
@@ -37,7 +37,7 @@ class ConfigTest extends UnitTestCase {
   /**
    * Event Dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -57,7 +57,7 @@ class ConfigTest extends UnitTestCase {
 
   protected function setUp(): void {
     $this->storage = $this->createMock('Drupal\Core\Config\StorageInterface');
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $this->typedConfig = $this->createMock('\Drupal\Core\Config\TypedConfigManagerInterface');
     $this->config = new Config('config.test', $this->storage, $this->eventDispatcher, $this->typedConfig);
     $this->cacheTagsInvalidator = $this->createMock('Drupal\Core\Cache\CacheTagsInvalidatorInterface');
diff --git a/core/tests/Drupal/Tests/Core/Config/ImmutableConfigTest.php b/core/tests/Drupal/Tests/Core/Config/ImmutableConfigTest.php
index 8b311948251..b8f92f0bf01 100644
--- a/core/tests/Drupal/Tests/Core/Config/ImmutableConfigTest.php
+++ b/core/tests/Drupal/Tests/Core/Config/ImmutableConfigTest.php
@@ -22,7 +22,7 @@ class ImmutableConfigTest extends UnitTestCase {
   protected function setUp(): void {
     parent::setUp();
     $storage = $this->createMock('Drupal\Core\Config\StorageInterface');
-    $event_dispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $event_dispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $typed_config = $this->createMock('Drupal\Core\Config\TypedConfigManagerInterface');
     $this->config = new ImmutableConfig('test', $storage, $event_dispatcher, $typed_config);
   }
diff --git a/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/MimeTypePassTest.php b/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/MimeTypePassTest.php
deleted file mode 100644
index 6526135f89e..00000000000
--- a/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/MimeTypePassTest.php
+++ /dev/null
@@ -1,63 +0,0 @@
-<?php
-
-namespace Drupal\Tests\Core\DependencyInjection\Compiler;
-
-use Drupal\Core\DependencyInjection\Compiler\MimeTypePass;
-use Drupal\Tests\UnitTestCase;
-use Symfony\Component\DependencyInjection\ContainerBuilder;
-use Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface as LegacyMimeTypeGuesserInterface;
-use Symfony\Component\Mime\MimeTypeGuesserInterface;
-use Drupal\Core\File\MimeType\MimeTypeGuesser;
-
-/**
- * @coversDefaultClass \Drupal\Core\DependencyInjection\Compiler\MimeTypePass
- * @group DependencyInjection
- * @group legacy
- * @runInSeparateProcess
- */
-class MimeTypePassTest extends UnitTestCase {
-
-  protected function buildContainer($environment = 'dev') {
-    $container = new ContainerBuilder();
-    $container->setParameter('kernel.environment', $environment);
-    return $container;
-  }
-
-  /**
-   * Tests backwards compatibility shim for MimeTypeGuesser interface changes.
-   *
-   * @expectedDeprecation The "Drupal\Tests\Core\DependencyInjection\Compiler\LegacyMimeTypeGuesser" class implements "Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface" that is deprecated since Symfony 4.3, use {@link MimeTypesInterface} instead.
-   */
-  public function testProcessLegacy() {
-    $container = $this->buildContainer();
-    $container
-      ->register('file.mime_type.guesser', MimeTypeGuesser::class);
-
-    $container
-      ->register('handler1', __NAMESPACE__ . '\NewMimeTypeGuesser')
-      ->addTag('mime_type_guesser');
-    $container
-      ->register('handler2', __NAMESPACE__ . '\LegacyMimeTypeGuesser')
-      ->addTag('mime_type_guesser');
-
-    $handler_pass = new MimeTypePass();
-    $handler_pass->process($container);
-    $method_calls = $container->getDefinition('file.mime_type.guesser')->getMethodCalls();
-    $this->assertCount(2, $method_calls);
-  }
-
-}
-
-class NewMimeTypeGuesser implements MimeTypeGuesserInterface {
-
-  public function guessMimeType(string $string): string {}
-
-  public function isGuesserSupported(): bool {}
-
-}
-
-class LegacyMimeTypeGuesser implements LegacyMimeTypeGuesserInterface {
-
-  public function guess($string) {}
-
-}
diff --git a/core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php b/core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
index 9456586b650..0980d883855 100644
--- a/core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
+++ b/core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
@@ -89,7 +89,7 @@ class EntityFieldManagerTest extends UnitTestCase {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\Prophecy\Prophecy\ProphecyInterface
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\Prophecy\Prophecy\ProphecyInterface
    */
   protected $eventDispatcher;
 
diff --git a/core/tests/Drupal/Tests/Core/Form/FormTestBase.php b/core/tests/Drupal/Tests/Core/Form/FormTestBase.php
index 56264ece281..c5db4a1f9de 100644
--- a/core/tests/Drupal/Tests/Core/Form/FormTestBase.php
+++ b/core/tests/Drupal/Tests/Core/Form/FormTestBase.php
@@ -115,7 +115,7 @@ abstract class FormTestBase extends UnitTestCase {
   /**
    * The event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $eventDispatcher;
 
@@ -174,7 +174,7 @@ protected function setUp() {
     $this->account = $this->createMock('Drupal\Core\Session\AccountInterface');
     $this->themeManager = $this->createMock('Drupal\Core\Theme\ThemeManagerInterface');
     $this->request = Request::createFromGlobals();
-    $this->eventDispatcher = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->eventDispatcher = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $this->requestStack = new RequestStack();
     $this->requestStack->push($this->request);
     $this->logger = $this->createMock('Drupal\Core\Logger\LoggerChannelInterface');
diff --git a/core/tests/Drupal/Tests/Core/Plugin/Discovery/ContainerDerivativeDiscoveryDecoratorTest.php b/core/tests/Drupal/Tests/Core/Plugin/Discovery/ContainerDerivativeDiscoveryDecoratorTest.php
index 938fbbc01b1..50e8ebcb1fa 100644
--- a/core/tests/Drupal/Tests/Core/Plugin/Discovery/ContainerDerivativeDiscoveryDecoratorTest.php
+++ b/core/tests/Drupal/Tests/Core/Plugin/Discovery/ContainerDerivativeDiscoveryDecoratorTest.php
@@ -15,7 +15,7 @@ class ContainerDerivativeDiscoveryDecoratorTest extends UnitTestCase {
    * @covers ::getDefinitions
    */
   public function testGetDefinitions() {
-    $example_service = $this->createMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $example_service = $this->createMock('Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $example_container = $this->getMockBuilder('Symfony\Component\DependencyInjection\ContainerBuilder')
       ->setMethods(['get'])
       ->getMock();
diff --git a/core/tests/Drupal/Tests/Core/Plugin/Discovery/TestContainerDerivativeDiscovery.php b/core/tests/Drupal/Tests/Core/Plugin/Discovery/TestContainerDerivativeDiscovery.php
index da7eed1962e..9c3c3c348c4 100644
--- a/core/tests/Drupal/Tests/Core/Plugin/Discovery/TestContainerDerivativeDiscovery.php
+++ b/core/tests/Drupal/Tests/Core/Plugin/Discovery/TestContainerDerivativeDiscovery.php
@@ -4,7 +4,7 @@
 
 use Drupal\Core\Plugin\Discovery\ContainerDeriverInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines container test derivative discovery.
@@ -14,7 +14,7 @@ class TestContainerDerivativeDiscovery extends TestDerivativeDiscovery implement
   /**
    * Constructs a TestContainerDerivativeDiscovery object.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface $example_service
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $example_service
    *   Some service.
    */
   public function __construct(EventDispatcherInterface $example_service) {
diff --git a/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php b/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
index 7682bfdd0f2..59d4367e7e3 100644
--- a/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
+++ b/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
@@ -47,7 +47,7 @@ class RouteBuilderTest extends UnitTestCase {
   /**
    * The mocked event dispatcher.
    *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
+   * @var \Symfony\Contracts\EventDispatcher\EventDispatcherInterface|\PHPUnit\Framework\MockObject\MockObject
    */
   protected $dispatcher;
 
@@ -80,7 +80,7 @@ class RouteBuilderTest extends UnitTestCase {
   protected function setUp(): void {
     $this->dumper = $this->createMock('Drupal\Core\Routing\MatcherDumperInterface');
     $this->lock = $this->createMock('Drupal\Core\Lock\LockBackendInterface');
-    $this->dispatcher = $this->createMock('\Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->dispatcher = $this->createMock('\Symfony\Contracts\EventDispatcher\EventDispatcherInterface');
     $this->moduleHandler = $this->createMock('Drupal\Core\Extension\ModuleHandlerInterface');
     $this->controllerResolver = $this->createMock('Drupal\Core\Controller\ControllerResolverInterface');
     $this->yamlDiscovery = $this->getMockBuilder('\Drupal\Core\Discovery\YamlDiscovery')
diff --git a/core/tests/Drupal/Tests/Core/Session/AccountProxyTest.php b/core/tests/Drupal/Tests/Core/Session/AccountProxyTest.php
index ae233a5cb91..47eaf96d4b5 100644
--- a/core/tests/Drupal/Tests/Core/Session/AccountProxyTest.php
+++ b/core/tests/Drupal/Tests/Core/Session/AccountProxyTest.php
@@ -5,7 +5,9 @@
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Session\AccountProxy;
 use Drupal\Tests\UnitTestCase;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Prophecy\Argument;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\EventDispatcher\Event;
 
 /**
  * @coversDefaultClass \Drupal\Core\Session\AccountProxy
@@ -19,6 +21,7 @@ class AccountProxyTest extends UnitTestCase {
    */
   public function testId() {
     $dispatcher = $this->prophesize(EventDispatcherInterface::class);
+    $dispatcher->dispatch(Argument::any(), Argument::any())->willReturn(new Event());
     $account_proxy = new AccountProxy($dispatcher->reveal());
     $this->assertSame(0, $account_proxy->id());
     $account_proxy->setInitialAccountId(1);
@@ -39,6 +42,7 @@ public function testId() {
   public function testSetInitialAccountIdException() {
     $this->expectException(\LogicException::class);
     $dispatcher = $this->prophesize(EventDispatcherInterface::class);
+    $dispatcher->dispatch(Argument::any(), Argument::any())->willReturn(new Event());
     $account_proxy = new AccountProxy($dispatcher->reveal());
     $current_user = $this->prophesize(AccountInterface::class);
     $account_proxy->setAccount($current_user->reveal());
diff --git a/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php b/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
index 64ffefb87ea..8a53ff01059 100644
--- a/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
+++ b/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
@@ -137,7 +137,14 @@ public static function getSkippedDeprecations() {
       'AssertLegacyTrait::assertFieldByXPath() is deprecated in drupal:8.3.0 and is removed from drupal:10.0.0. Use $this->xpath() instead and check the values directly in the test. See https://www.drupal.org/node/3129738',
       'AssertLegacyTrait::assertNoFieldByXPath() is deprecated in drupal:8.3.0 and is removed from drupal:10.0.0. Use $this->xpath() instead and assert that the result is empty. See https://www.drupal.org/node/3129738',
       'AssertLegacyTrait::assertFieldsByValue() is deprecated in drupal:8.3.0 and is removed from drupal:10.0.0. Use iteration over the fields yourself instead and directly check the values in the test. See https://www.drupal.org/node/3129738',
+      // Deprecation introduced in Symfony 5
+      'Since symfony/dependency-injection 5.1: The signature of method "Symfony\Component\DependencyInjection\Alias::setDeprecated()" requires 3 arguments: "string $package, string $version, string $message", not defining them is deprecated.',
+      'Since symfony/dependency-injection 5.1: The signature of method "Symfony\Component\DependencyInjection\Definition::setDeprecated()" requires 3 arguments: "string $package, string $version, string $message", not defining them is deprecated.',
+      'Since symfony/http-foundation 5.1: Retrieving a non-string value from "Symfony\Component\HttpFoundation\InputBag::get()" is deprecated, and will throw a "Symfony\Component\HttpFoundation\Exception\BadRequestException" exception in Symfony 6.0, use "Symfony\Component\HttpFoundation\InputBag::all($key)" instead.'
     ];
+
+    // Deprecations introduced in Symfony 5
+
   }
 
   /**