diff --git a/core/modules/editor/src/EditorXssFilter/Standard.php b/core/modules/editor/src/EditorXssFilter/Standard.php
index 19d5c06..363497f 100644
--- a/core/modules/editor/src/EditorXssFilter/Standard.php
+++ b/core/modules/editor/src/EditorXssFilter/Standard.php
@@ -19,7 +19,7 @@ public static function filterXss($html, FilterFormatInterface $format, FilterFor
     // Apply XSS filtering, but blacklist the <script>, <style>, <link>, <embed>
     // and <object> tags.
     // The <script> and <style> tags are blacklisted because their contents
-    // can be malicious (and therefor they are inherently unsafe), whereas for
+    // can be malicious (and therefore they are inherently unsafe), whereas for
     // all other tags, only their attributes can make them malicious. Since
     // \Drupal\Component\Utility\Xss::filter() protects against malicious
     // attributes, we take no blacklisting action.
@@ -41,10 +41,10 @@ public static function filterXss($html, FilterFormatInterface $format, FilterFor
     // also user frustration: what if a text format is configured to allow
     // <embed>, for example? Then we would strip that tag, even though it is
     // allowed, thereby causing data loss!
-    // Therefor, we want to be smarter still. We want to take into account which
-    // HTML tags are allowed and forbidden by the text format we're filtering
-    // for, and if we're switching from another text format, we want to take
-    // that format's allowed and forbidden tags into account as well.
+    // Therefore, we want to be smarter still. We want to take into account
+    // which HTML tags are allowed and forbidden by the text format we're
+    // filtering for, and if we're switching from another text format, we want
+    // to take that format's allowed and forbidden tags into account as well.
     // In other words: we only expect markup allowed in both the original and
     // the new format to continue to exist.
     $format_restrictions = $format->getHtmlRestrictions();
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php b/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
index 66e1abb..aa0044b 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
@@ -74,7 +74,7 @@ public function testChanged() {
 
     // We can't assert equality here because the created time is set to the
     // request time, while instances of ChangedTestItem use the current
-    // timestamp every time. Therefor we check if the changed timestamp is
+    // timestamp every time. Therefore we check if the changed timestamp is
     // between the created time and now.
     $this->assertTrue(
       ($entity->getChangedTime() >= $entity->get('created')->value) &&
diff --git a/core/tests/Drupal/Tests/Core/EventSubscriber/ActiveLinkResponseFilterTest.php b/core/tests/Drupal/Tests/Core/EventSubscriber/ActiveLinkResponseFilterTest.php
index f60fe68..4d3d507 100644
--- a/core/tests/Drupal/Tests/Core/EventSubscriber/ActiveLinkResponseFilterTest.php
+++ b/core/tests/Drupal/Tests/Core/EventSubscriber/ActiveLinkResponseFilterTest.php
@@ -42,7 +42,7 @@ public function providerTestSetLinkActiveClass() {
       'a',
       // Unfortunately, it must also work on list items.
       'li',
-      // … and therefor, on *any* tag, really.
+      // … and therefore, on *any* tag, really.
       'foo',
     ];
     $contents = [