diff -u b/core/modules/aggregator/tests/src/Functional/AddFeedTest.php b/core/modules/aggregator/tests/src/Functional/AddFeedTest.php
--- b/core/modules/aggregator/tests/src/Functional/AddFeedTest.php
+++ b/core/modules/aggregator/tests/src/Functional/AddFeedTest.php
@@ -64,7 +64,7 @@
     $this->assertSession()->statusCodeEquals(200);

     $this->assertEscaped('Test feed title <script>alert(123);</script>');
-    $this->assertNoRaw('Test feed title <script>alert(123);</script>');
+    $this->assertSession()->responseNotContains('Test feed title <script>alert(123);</script>');

     // Ensure the feed icon title is escaped.
     $this->assertStringContainsString('class="feed-icon">  Subscribe to Test feed title &lt;script&gt;alert(123);&lt;/script&gt; feed</a>', str_replace(["\n", "\r"], '', $this->getSession()->getPage()->getContent()));
diff -u b/core/modules/big_pipe/tests/src/Functional/BigPipeTest.php b/core/modules/big_pipe/tests/src/Functional/BigPipeTest.php
--- b/core/modules/big_pipe/tests/src/Functional/BigPipeTest.php
+++ b/core/modules/big_pipe/tests/src/Functional/BigPipeTest.php
@@ -87,18 +87,18 @@
     $this->drupalGet(Url::fromRoute('<front>'));
     $this->assertSessionCookieExists(FALSE);
     $this->assertBigPipeNoJsCookieExists(FALSE);
-    $this->assertNoRaw('<noscript><meta http-equiv="Refresh" content="0; URL=');
-    $this->assertNoRaw($no_js_to_js_markup);
+    $this->assertSession()->responseNotContains('<noscript><meta http-equiv="Refresh" content="0; URL=');
+    $this->assertSession()->responseNotContains($no_js_to_js_markup);

     // 2. Session (authenticated).
     $this->drupalLogin($this->rootUser);
     $this->assertSessionCookieExists(TRUE);
     $this->assertBigPipeNoJsCookieExists(FALSE);
     $this->assertSession()->responseContains('<noscript><meta http-equiv="Refresh" content="0; URL=' . base_path() . 'big_pipe/no-js?destination=' . base_path() . 'user/1" />' . "\n" . '</noscript>');
-    $this->assertNoRaw($no_js_to_js_markup);
+    $this->assertSession()->responseNotContains($no_js_to_js_markup);
     $this->assertBigPipeNoJsMetaRefreshRedirect();
     $this->assertBigPipeNoJsCookieExists(TRUE);
-    $this->assertNoRaw('<noscript><meta http-equiv="Refresh" content="0; URL=');
+    $this->assertSession()->responseNotContains('<noscript><meta http-equiv="Refresh" content="0; URL=');
     $this->assertSession()->responseContains($no_js_to_js_markup);
     $this->drupalLogout();

@@ -111,10 +111,10 @@
     $this->assertSessionCookieExists(TRUE);
     $this->assertBigPipeNoJsCookieExists(FALSE);
     $this->assertSession()->responseContains('<noscript><meta http-equiv="Refresh" content="0; URL=' . base_path() . 'big_pipe/no-js?destination=' . base_path() . 'user/login" />' . "\n" . '</noscript>');
-    $this->assertNoRaw($no_js_to_js_markup);
+    $this->assertSession()->responseNotContains($no_js_to_js_markup);
     $this->assertBigPipeNoJsMetaRefreshRedirect();
     $this->assertBigPipeNoJsCookieExists(TRUE);
-    $this->assertNoRaw('<noscript><meta http-equiv="Refresh" content="0; URL=');
+    $this->assertSession()->responseNotContains('<noscript><meta http-equiv="Refresh" content="0; URL=');
     $this->assertSession()->responseContains($no_js_to_js_markup);

     // Close the prior connection and remove the collected state.
@@ -124,14 +124,14 @@
     $this->drupalGet(Url::fromRoute('no_big_pipe'));
     $this->assertSessionCookieExists(FALSE);
     $this->assertBigPipeNoJsCookieExists(FALSE);
-    $this->assertNoRaw('<noscript><meta http-equiv="Refresh" content="0; URL=');
-    $this->assertNoRaw($no_js_to_js_markup);
+    $this->assertSession()->responseNotContains('<noscript><meta http-equiv="Refresh" content="0; URL=');
+    $this->assertSession()->responseNotContains($no_js_to_js_markup);
     $this->drupalLogin($this->rootUser);
     $this->drupalGet(Url::fromRoute('no_big_pipe'));
     $this->assertSessionCookieExists(TRUE);
     $this->assertBigPipeNoJsCookieExists(FALSE);
-    $this->assertNoRaw('<noscript><meta http-equiv="Refresh" content="0; URL=');
-    $this->assertNoRaw($no_js_to_js_markup);
+    $this->assertSession()->responseNotContains('<noscript><meta http-equiv="Refresh" content="0; URL=');
+    $this->assertSession()->responseNotContains($no_js_to_js_markup);
   }

   /**
@@ -211,8 +211,8 @@
     // The 'edge_case__html_exception' case throws an exception.
     $this->assertSession()->responseContains('The website encountered an unexpected error. Please try again later');
     $this->assertSession()->responseContains('You are not allowed to say llamas are not cool!');
-    $this->assertNoRaw(BigPipe::STOP_SIGNAL, 'BigPipe stop signal absent: error occurred before then.');
-    $this->assertNoRaw('</body>', 'Closing body tag absent: error occurred before then.');
+    $this->assertSession()->responseNotContains(BigPipe::STOP_SIGNAL, 'BigPipe stop signal absent: error occurred before then.');
+    $this->assertSession()->responseNotContains('</body>', 'Closing body tag absent: error occurred before then.');
     // The exception is expected. Do not interpret it as a test failure.
     unlink($this->root . '/' . $this->siteDirectory . '/error.log');
   }
@@ -262,8 +262,8 @@
     $this->pass('Verifying there are no BigPipe placeholders & replacements…', 'Debug');
     $this->assertEqual('<none>', $this->drupalGetHeader('BigPipe-Test-Placeholders'));
     $this->pass('Verifying BigPipe start/stop signals are absent…', 'Debug');
-    $this->assertNoRaw(BigPipe::START_SIGNAL, 'BigPipe start signal absent.');
-    $this->assertNoRaw(BigPipe::STOP_SIGNAL, 'BigPipe stop signal absent.');
+    $this->assertSession()->responseNotContains(BigPipe::START_SIGNAL, 'BigPipe start signal absent.');
+    $this->assertSession()->responseNotContains(BigPipe::STOP_SIGNAL, 'BigPipe stop signal absent.');

     $this->pass('Verifying BigPipe assets are absent…', 'Debug');
     $this->assertTrue(!isset($this->getDrupalSettings()['bigPipePlaceholderIds']) && empty($this->getDrupalSettings()['ajaxPageState']), 'BigPipe drupalSettings and BigPipe asset library absent.');
@@ -280,7 +280,7 @@
     // The 'edge_case__html_exception' case throws an exception.
     $this->assertSession()->responseContains('The website encountered an unexpected error. Please try again later');
     $this->assertSession()->responseContains('You are not allowed to say llamas are not cool!');
-    $this->assertNoRaw('</body>', 'Closing body tag absent: error occurred before then.');
+    $this->assertSession()->responseNotContains('</body>', 'Closing body tag absent: error occurred before then.');
     // The exception is expected. Do not interpret it as a test failure.
     unlink($this->root . '/' . $this->siteDirectory . '/error.log');
   }
@@ -303,8 +303,8 @@
     $big_pipe_placeholder_id = 'callback=Drupal%5CCore%5CRender%5CElement%5CStatusMessages%3A%3ArenderMessages&amp;args%5B0%5D&amp;token=_HAdUpwWmet0TOTe2PSiJuMntExoshbm1kh2wQzzzAA';
     $expected_placeholder_replacement = '<script type="application/vnd.drupal-ajax" data-big-pipe-replacement-for-placeholder-with-id="' . $big_pipe_placeholder_id . '">';
     $this->assertSession()->responseContains('The count is 1.');
-    $this->assertNoRaw('The count is 2.');
-    $this->assertNoRaw('The count is 3.');
+    $this->assertSession()->responseNotContains('The count is 2.');
+    $this->assertSession()->responseNotContains('The count is 3.');
     $raw_content = $this->getSession()->getPage()->getContent();
     $this->assertTrue(substr_count($raw_content, $expected_placeholder_replacement) == 1, 'Only one placeholder replacement was found for the duplicate #lazy_builder arrays.');

@@ -317,8 +317,8 @@
     $this->assertBigPipeNoJsCookieExists(TRUE);
     $this->drupalGet(Url::fromRoute('big_pipe_test_multi_occurrence'));
     $this->assertSession()->responseContains('The count is 1.');
-    $this->assertNoRaw('The count is 2.');
-    $this->assertNoRaw('The count is 3.');
+    $this->assertSession()->responseNotContains('The count is 2.');
+    $this->assertSession()->responseNotContains('The count is 3.');
   }

   protected function assertBigPipeResponseHeadersPresent() {
@@ -341,7 +341,7 @@
     $this->assertSetsEqual(array_keys($expected_big_pipe_nojs_placeholders), array_map('rawurldecode', explode(' ', $this->drupalGetHeader('BigPipe-Test-No-Js-Placeholders'))));
     foreach ($expected_big_pipe_nojs_placeholders as $big_pipe_nojs_placeholder => $expected_replacement) {
       $this->pass('Checking whether the replacement for the BigPipe no-JS placeholder "' . $big_pipe_nojs_placeholder . '" is present:');
-      $this->assertNoRaw($big_pipe_nojs_placeholder);
+      $this->assertSession()->responseNotContains($big_pipe_nojs_placeholder);
       if ($expected_replacement !== NULL) {
         $this->assertSession()->responseContains($expected_replacement);
       }
@@ -374,7 +374,7 @@
       $result = $this->xpath('//script[@data-big-pipe-replacement-for-placeholder-with-id=:id]', [':id' => Html::decodeEntities($big_pipe_placeholder_id)]);
       if ($expected_ajax_response === NULL) {
         $this->assertCount(0, $result);
-        $this->assertNoRaw($expected_placeholder_replacement);
+        $this->assertSession()->responseNotContains($expected_placeholder_replacement);
         continue;
       }
       $this->assertEqual($expected_ajax_response, trim($result[0]->getText()));
@@ -490,7 +490,7 @@
     $this->assertTrue(empty(array_diff(['cookies:big_pipe_nojs', 'session.exists'], explode(' ', $headers[0]['X-Drupal-Cache-Contexts'][0]))), 'The first response varies by the "cookies:big_pipe_nojs" and "session.exists" cache contexts.');
     $this->assertEqual('no-store, content="BigPipe/1.0"', $headers[1]['Surrogate-Control'][0], 'The second response has a "Surrogate-Control" header.');

-    $this->assertNoRaw('<noscript><meta http-equiv="Refresh" content="0; URL=', 'Once the BigPipe no-JS cookie is set, the <meta> refresh is absent: only one redirect ever happens.');
+    $this->assertSession()->responseNotContains('<noscript><meta http-equiv="Refresh" content="0; URL=', 'Once the BigPipe no-JS cookie is set, the <meta> refresh is absent: only one redirect ever happens.');
   }

 }
diff -u b/core/modules/block/tests/src/Functional/BlockInvalidRegionTest.php b/core/modules/block/tests/src/Functional/BlockInvalidRegionTest.php
--- b/core/modules/block/tests/src/Functional/BlockInvalidRegionTest.php
+++ b/core/modules/block/tests/src/Functional/BlockInvalidRegionTest.php
@@ -53,7 +53,7 @@

     // Clear the cache to check if the warning message is not triggered.
     $this->drupalPostForm('admin/config/development/performance', [], 'Clear all caches');
-    $this->assertNoRaw($warning_message, 'Disabled block in the invalid region will not trigger the warning.');
+    $this->assertSession()->responseNotContains($warning_message, 'Disabled block in the invalid region will not trigger the warning.');

     // Place disabled test block in the invalid region of the default theme.
     \Drupal::configFactory()->getEditable('block.block.' . $block->id())->set('region', 'invalid_region')->save();
@@ -61,7 +61,7 @@

     // Clear the cache to check if the warning message is not triggered.
     $this->drupalPostForm('admin/config/development/performance', [], 'Clear all caches');
-    $this->assertNoRaw($warning_message, 'Disabled block in the invalid region will not trigger the warning.');
+    $this->assertSession()->responseNotContains($warning_message, 'Disabled block in the invalid region will not trigger the warning.');
   }

 }
diff -u b/core/modules/block/tests/src/Functional/BlockTest.php b/core/modules/block/tests/src/Functional/BlockTest.php
--- b/core/modules/block/tests/src/Functional/BlockTest.php
+++ b/core/modules/block/tests/src/Functional/BlockTest.php
@@ -63,7 +63,7 @@

     // Confirm that an empty block is not displayed.
     $this->assertNoText('Powered by Drupal', 'Empty block not displayed.');
-    $this->assertNoRaw('sidebar-first', 'Empty sidebar-first region is not displayed.');
+    $this->assertSession()->responseNotContains('sidebar-first', 'Empty sidebar-first region is not displayed.');
   }

   /**
@@ -241,7 +241,7 @@
     $this->drupalPostForm(NULL, [], t('Remove'));
     $this->assertSession()->responseContains(t('The block %name has been removed.', ['%name' => $block->label()]));
     $this->assertUrl('admin');
-    $this->assertNoRaw($block->id());
+    $this->assertSession()->responseNotContains($block->id());
   }

   /**
diff -u b/core/modules/block/tests/src/Functional/BlockUiTest.php b/core/modules/block/tests/src/Functional/BlockUiTest.php
--- b/core/modules/block/tests/src/Functional/BlockUiTest.php
+++ b/core/modules/block/tests/src/Functional/BlockUiTest.php
@@ -229,7 +229,7 @@
     $expected_text = '<div id="test_context_aware--username">' . \Drupal::currentUser()->getAccountName() . '</div>';
     $this->drupalGet('');
     $this->assertNoText('Test context-aware block');
-    $this->assertNoRaw($expected_text);
+    $this->assertSession()->responseNotContains($expected_text);

     $block_url = 'admin/structure/block/add/test_context_aware/classy';
     $arguments = [
@@ -275,7 +275,7 @@

     // Tests that conditions with missing context are not displayed.
     $this->drupalGet('admin/structure/block/manage/testcontextawareblock');
-    $this->assertNoRaw('No existing type');
+    $this->assertSession()->responseNotContains('No existing type');
     $this->assertNoFieldByXPath('//*[@name="visibility[condition_test_no_existing_type][negate]"]');
   }

diff -u b/core/modules/block_content/tests/src/Functional/BlockContentCreationTest.php b/core/modules/block_content/tests/src/Functional/BlockContentCreationTest.php
--- b/core/modules/block_content/tests/src/Functional/BlockContentCreationTest.php
+++ b/core/modules/block_content/tests/src/Functional/BlockContentCreationTest.php
@@ -264,7 +264,7 @@
     $edit2['body[0][value]'] = $body2;
     $this->drupalPostForm('block/add/basic', $edit2, t('Save'));

-    $this->assertNoRaw('Error message');
+    $$this->assertSession()->responseNotContains(t('Error message'));

     // Create another block with no instances, and test we don't get a
     // confirmation message about deleting instances.
diff -u b/core/modules/color/tests/src/Functional/ColorSafePreviewTest.php b/core/modules/color/tests/src/Functional/ColorSafePreviewTest.php
--- b/core/modules/color/tests/src/Functional/ColorSafePreviewTest.php
+++ b/core/modules/color/tests/src/Functional/ColorSafePreviewTest.php
@@ -55,7 +55,7 @@
     $this->drupalGet($url);
     $this->assertText('TEST COLOR PREVIEW');

-    $this->assertNoRaw('<script>alert("security filter test");</script>');
+    $this->assertSession()->responseNotContains('<script>alert("security filter test");</script>');
     $this->assertSession()->responseContains('<h2>TEST COLOR PREVIEW</h2>');
   }

diff -u b/core/modules/color/tests/src/Functional/ColorTest.php b/core/modules/color/tests/src/Functional/ColorTest.php
--- b/core/modules/color/tests/src/Functional/ColorTest.php
+++ b/core/modules/color/tests/src/Functional/ColorTest.php
@@ -207,7 +207,7 @@
     $this->drupalPlaceBlock('system_branding_block', ['region' => 'header']);

     $this->drupalGet('');
-    $this->assertNoRaw('files/color/bartik-', 'Make sure the color logo is not being used.');
+    $this->assertSession()->responseNotContains('files/color/bartik-', 'Make sure the color logo is not being used.');
     $this->assertSession()->responseContains('bartik/logo.svg', 'Make sure the original bartik logo exists.');

     // Log in and set the color scheme to 'slate'.
@@ -219,7 +219,7 @@
     $this->drupalLogout();
     $this->drupalGet('');
     $this->assertSession()->responseContains('files/color/bartik-', 'Make sure the color logo is being used.');
-    $this->assertNoRaw('bartik/logo.svg', 'Make sure the original bartik logo does not exist.');
+    $this->assertSession()->responseNotContains('bartik/logo.svg', 'Make sure the original bartik logo does not exist.');

     // Log in and set the color scheme back to default (delete config).
     $this->drupalLogin($this->bigUser);
@@ -229,7 +229,7 @@
     // Log out and ensure there is no color and we have the original logo.
     $this->drupalLogout();
     $this->drupalGet('');
-    $this->assertNoRaw('files/color/bartik-', 'Make sure the color logo is not being used.');
+    $this->assertSession()->responseNotContains('files/color/bartik-', 'Make sure the color logo is not being used.');
     $this->assertSession()->responseContains('bartik/logo.svg', 'Make sure the original bartik logo exists.');
   }

diff -u b/core/modules/comment/tests/src/Functional/CommentAnonymousTest.php b/core/modules/comment/tests/src/Functional/CommentAnonymousTest.php
--- b/core/modules/comment/tests/src/Functional/CommentAnonymousTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentAnonymousTest.php
@@ -157,7 +157,7 @@
     $this->performCommentOperation($anonymous_comment3, 'delete');

     $this->drupalGet('admin/content/comment');
-    $this->assertNoRaw('comments[' . $anonymous_comment3->id() . ']', 'Comment was deleted.');
+    $this->assertSession()->responseNotContains('comments[' . $anonymous_comment3->id() . ']', 'Comment was deleted.');
     $this->drupalLogout();

     // Comment 3 was deleted.
diff -u b/core/modules/comment/tests/src/Functional/CommentInterfaceTest.php b/core/modules/comment/tests/src/Functional/CommentInterfaceTest.php
--- b/core/modules/comment/tests/src/Functional/CommentInterfaceTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentInterfaceTest.php
@@ -344,7 +344,7 @@
     // mode this time.
     $comment_element = $this->cssSelect('.comment-wrapper');
     $this->assertTrue(!empty($comment_element));
-    $this->assertNoRaw('<p>' . $comment_text . '</p>');
+    $this->assertSession()->responseNotContains('<p>' . $comment_text . '</p>');
   }

 }
diff -u b/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php b/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
--- b/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
@@ -323,7 +323,7 @@
     // Delete the comment.
     $this->performCommentOperation($comment1, 'delete');
     $this->drupalGet('admin/content/comment');
-    $this->assertNoRaw('comments[' . $comment1->id() . ']', 'Comment was deleted.');
+    $this->assertSession()->responseNotContains('comments[' . $comment1->id() . ']', 'Comment was deleted.');

     // Post another comment.
     $comment1 = $this->postComment($this->entity, $this->randomMachineName(), $this->randomMachineName());
diff -u b/core/modules/comment/tests/src/Functional/CommentRssTest.php b/core/modules/comment/tests/src/Functional/CommentRssTest.php
--- b/core/modules/comment/tests/src/Functional/CommentRssTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentRssTest.php
@@ -78,7 +78,7 @@
     $this->node->set('comment', CommentItemInterface::HIDDEN);
     $this->node->save();
     $this->drupalGet('rss.xml');
-    $this->assertNoRaw($raw, 'Hidden comments is not a part of RSS feed.');
+    $this->assertSession()->responseNotContains($raw, 'Hidden comments is not a part of RSS feed.');
   }

 }
diff -u b/core/modules/config/tests/src/Functional/ConfigEntityListTest.php b/core/modules/config/tests/src/Functional/ConfigEntityListTest.php
--- b/core/modules/config/tests/src/Functional/ConfigEntityListTest.php
+++ b/core/modules/config/tests/src/Functional/ConfigEntityListTest.php
@@ -273,11 +273,11 @@

     // Item 51 should not be present.
     $this->assertSession()->responseContains('Test config entity 50', 'Config entity 50 is shown.');
-    $this->assertNoRaw('Test config entity 51', 'Config entity 51 is on the next page.');
+    $this->assertSession()->responseNotContains('Test config entity 51', 'Config entity 51 is on the next page.');

     // Browse to the next page.
     $this->clickLink(t('Page 2'));
-    $this->assertNoRaw('Test config entity 50', 'Test config entity 50 is on the previous page.');
+    $this->assertSession()->responseNotContains('Test config entity 50', 'Test config entity 50 is on the previous page.');
     $this->assertSession()->responseContains('dotted.default', 'Default config entity appears on page 2.');
     $this->assertSession()->responseContains('Test config entity 51', 'Test config entity 51 is on page 2.');
   }
diff -u b/core/modules/config/tests/src/Functional/ConfigEntityTest.php b/core/modules/config/tests/src/Functional/ConfigEntityTest.php
--- b/core/modules/config/tests/src/Functional/ConfigEntityTest.php
+++ b/core/modules/config/tests/src/Functional/ConfigEntityTest.php
@@ -255,7 +255,7 @@
     $this->assertUrl('admin/structure/config_test');
     $this->assertSession()->statusCodeEquals(200);
     $this->assertSession()->responseContains($message_insert);
-    $this->assertNoRaw($message_update);
+    $this->assertSession()->responseNotContains($message_update);
     $this->assertLinkByHref("admin/structure/config_test/manage/$id");

     // Update the configuration entity.
@@ -265,7 +265,7 @@
     $this->drupalPostForm("admin/structure/config_test/manage/$id", $edit, 'Save');
     $this->assertUrl('admin/structure/config_test');
     $this->assertSession()->statusCodeEquals(200);
-    $this->assertNoRaw($message_insert);
+    $this->assertSession()->responseNotContains($message_insert);
     $this->assertSession()->responseContains($message_update);
     $this->assertLinkByHref("admin/structure/config_test/manage/$id");
     $this->assertLinkByHref("admin/structure/config_test/manage/$id/delete");
@@ -277,7 +277,7 @@
     $this->drupalPostForm(NULL, [], 'Delete');
     $this->assertUrl('admin/structure/config_test');
     $this->assertSession()->statusCodeEquals(200);
-    $this->assertNoRaw($message_update);
+    $this->assertSession()->responseNotContains($message_update);
     $this->assertSession()->responseContains($message_delete);
     $this->assertNoText($label1);
     $this->assertNoLinkByHref("admin/structure/config_test/manage/$id");
diff -u b/core/modules/config/tests/src/Functional/ConfigImportUITest.php b/core/modules/config/tests/src/Functional/ConfigImportUITest.php
--- b/core/modules/config/tests/src/Functional/ConfigImportUITest.php
+++ b/core/modules/config/tests/src/Functional/ConfigImportUITest.php
@@ -130,11 +130,11 @@

     // Import and verify that both do not appear anymore.
     $this->drupalPostForm(NULL, [], t('Import all'));
-    $this->assertNoRaw('<td>' . $name);
-    $this->assertNoRaw('<td>' . $dynamic_name);
-    $this->assertNoRaw('<td>core.extension');
-    $this->assertNoRaw('<td>system.theme');
-    $this->assertNoRaw('<td>automated_cron.settings');
+    $this->assertSession()->responseNotContains('<td>' . $name);
+    $this->assertSession()->responseNotContains('<td>' . $dynamic_name);
+    $this->assertSession()->responseNotContains('<td>core.extension');
+    $this->assertSession()->responseNotContains('<td>system.theme');
+    $this->assertSession()->responseNotContains('<td>automated_cron.settings');

     $this->assertNoFieldById('edit-submit', t('Import all'));

@@ -201,9 +201,9 @@

     // Import and verify that both do not appear anymore.
     $this->drupalPostForm(NULL, [], t('Import all'));
-    $this->assertNoRaw('<td>core.extension');
-    $this->assertNoRaw('<td>system.theme');
-    $this->assertNoRaw('<td>automated_cron.settings');
+    $this->assertSession()->responseNotContains('<td>core.extension');
+    $this->assertSession()->responseNotContains('<td>system.theme');
+    $this->assertSession()->responseNotContains('<td>automated_cron.settings');

     $this->rebuildContainer();
     $this->assertFalse(\Drupal::moduleHandler()->moduleExists('ban'), 'Ban module uninstalled during import.');
@@ -300,7 +300,7 @@

     // Load the diff UI and verify that the diff reflects the change.
     $this->drupalGet('admin/config/development/configuration/sync/diff/' . $config_name);
-    $this->assertNoRaw('&amp;nbsp;');
+    $this->assertSession()->responseNotContains('&amp;nbsp;');
     $this->assertSession()->titleEquals("View changes of $config_name | Drupal");

     // The following assertions do not use $this::assertEscaped() because
@@ -483,7 +483,7 @@
     // Delete the node and try to import again.
     $node->delete();
     $this->drupalPostForm(NULL, [], t('Import all'));
-    $this->assertNoRaw($validation_message);
+    $this->assertSession()->responseNotContains($validation_message);
     $this->assertText(t('There are no configuration changes to import.'));
     $this->assertNoText(new FormattableMarkup('node.type.@type', ['@type' => $node_type->id()]));
     $this->assertNoText(new FormattableMarkup('field.field.node.@type.body', ['@type' => $node_type->id()]));
diff -u b/core/modules/config_translation/tests/src/Functional/ConfigTranslationUiTest.php b/core/modules/config_translation/tests/src/Functional/ConfigTranslationUiTest.php
--- b/core/modules/config_translation/tests/src/Functional/ConfigTranslationUiTest.php
+++ b/core/modules/config_translation/tests/src/Functional/ConfigTranslationUiTest.php
@@ -671,7 +671,7 @@
           $this->assertSession()->responseContains('edit-source-config-names-viewsviewfiles-display-default-display-options-fields-count-format-plural-string-' . $index);
         }
         else {
-          $this->assertNoRaw('edit-source-config-names-viewsviewfiles-display-default-display-options-fields-count-format-plural-string-' . $index);
+          $this->assertSession()->responseNotContains('edit-source-config-names-viewsviewfiles-display-default-display-options-fields-count-format-plural-string-' . $index);
         }
       }
     }
diff -u b/core/modules/contact/tests/src/Functional/ContactPersonalTest.php b/core/modules/contact/tests/src/Functional/ContactPersonalTest.php
--- b/core/modules/contact/tests/src/Functional/ContactPersonalTest.php
+++ b/core/modules/contact/tests/src/Functional/ContactPersonalTest.php
@@ -107,7 +107,7 @@
     ];
     $this->assertSession()->responseContains(new FormattableMarkup('@sender_name (@sender_email) sent @recipient_name an email.', $placeholders));
     // Ensure an unescaped version of the email does not exist anywhere.
-    $this->assertNoRaw($this->webUser->getEmail());
+    $this->assertSession()->responseNotContains($this->webUser->getEmail());
   }

   /**
diff -u b/core/modules/content_translation/tests/src/Functional/ContentTranslationEnableTest.php b/core/modules/content_translation/tests/src/Functional/ContentTranslationEnableTest.php
--- b/core/modules/content_translation/tests/src/Functional/ContentTranslationEnableTest.php
+++ b/core/modules/content_translation/tests/src/Functional/ContentTranslationEnableTest.php
@@ -45,7 +45,7 @@

     $this->drupalGet('admin/config/regional/content-language');
     // The node entity type should not be an option because it has no bundles.
-    $this->assertNoRaw('entity_types[node]');
+    $this->assertSession()->responseNotContains('entity_types[node]');
     // Enable content translation on entity types that have will have a
     // content_translation_uid.
     $edit = [
diff -u b/core/modules/content_translation/tests/src/Functional/ContentTranslationUITestBase.php b/core/modules/content_translation/tests/src/Functional/ContentTranslationUITestBase.php
--- b/core/modules/content_translation/tests/src/Functional/ContentTranslationUITestBase.php
+++ b/core/modules/content_translation/tests/src/Functional/ContentTranslationUITestBase.php
@@ -115,7 +115,7 @@

     // Assert that HTML is not escaped unexpectedly.
     if ($this->testHTMLEscapeForAllLanguages) {
-      $this->assertNoRaw('&lt;span class=&quot;translation-entity-all-languages&quot;&gt;(all languages)&lt;/span&gt;');
+      $this->assertSession()->responseNotContains('&lt;span class=&quot;translation-entity-all-languages&quot;&gt;(all languages)&lt;/span&gt;');
       $this->assertSession()->responseContains('<span class="translation-entity-all-languages">(all languages)</span>');
     }

diff -u b/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php b/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php
--- b/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php
+++ b/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php
@@ -78,7 +78,7 @@
       $id = $match[1];
       $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
       $this->assertSession()->responseContains($date->format($date_format));
-      $this->assertNoRaw($date->format($time_format));
+      $this->assertSession()->responseNotContains($date->format($time_format));

       // Verify the date doesn't change if using a timezone that is UTC+12 when
       // the entity is edited through the form.
diff -u b/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php b/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php
--- b/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php
+++ b/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php
@@ -94,9 +94,9 @@
       $id = $match[1];
       $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
       $this->assertSession()->responseContains($start_date->format($date_format));
-      $this->assertNoRaw($start_date->format($time_format));
+      $this->assertSession()->responseNotContains($start_date->format($time_format));
       $this->assertSession()->responseContains($end_date->format($date_format));
-      $this->assertNoRaw($end_date->format($time_format));
+      $this->assertSession()->responseNotContains($end_date->format($time_format));

       // Verify the date doesn't change when entity is edited through the form.
       $entity = EntityTest::load($id);
@@ -500,9 +500,9 @@
     $id = $match[1];
     $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
     $this->assertSession()->responseContains($start_date->format($date_format));
-    $this->assertNoRaw($start_date->format($time_format));
+    $this->assertSession()->responseNotContains($start_date->format($time_format));
     $this->assertSession()->responseContains($end_date->format($date_format));
-    $this->assertNoRaw($end_date->format($time_format));
+    $this->assertSession()->responseNotContains($end_date->format($time_format));

     /** @var \Drupal\Core\Entity\EntityDisplayRepositoryInterface $display_repository */
     $display_repository = \Drupal::service('entity_display.repository');
diff -u b/core/modules/dblog/tests/src/Functional/DbLogTest.php b/core/modules/dblog/tests/src/Functional/DbLogTest.php
--- b/core/modules/dblog/tests/src/Functional/DbLogTest.php
+++ b/core/modules/dblog/tests/src/Functional/DbLogTest.php
@@ -824,13 +824,13 @@
     $this->assertSession()->statusCodeEquals(200);
     // Make sure HTML tags are filtered out.
     $this->assertSession()->responseContains('title="alert(&#039;foo&#039;);Lorem');
-    $this->assertNoRaw("<script>alert('foo');</script>");
+    $this->assertSession()->responseNotContains("<script>alert('foo');</script>");

     // Make sure HTML tags are filtered out in admin/reports/dblog/event/ too.
     $this->generateLogEntries(1, ['message' => "<script>alert('foo');</script> <strong>Lorem ipsum</strong>"]);
     $wid = Database::getConnection()->query('SELECT MAX(wid) FROM {watchdog}')->fetchField();
     $this->drupalGet('admin/reports/dblog/event/' . $wid);
-    $this->assertNoRaw("<script>alert('foo');</script>");
+    $this->assertSession()->responseNotContains("<script>alert('foo');</script>");
     $this->assertSession()->responseContains("alert('foo'); <strong>Lorem ipsum</strong>");
   }

diff -u b/core/modules/editor/tests/src/Functional/EditorAdminTest.php b/core/modules/editor/tests/src/Functional/EditorAdminTest.php
--- b/core/modules/editor/tests/src/Functional/EditorAdminTest.php
+++ b/core/modules/editor/tests/src/Functional/EditorAdminTest.php
@@ -203,7 +203,7 @@
     $this->assertTrue(($options[1]->getText()) === 'Unicorn Editor', 'Option 2 in the Text Editor select is "Unicorn Editor".');
     $this->assertTrue($options[0]->hasAttribute('selected'), 'Option 1 ("None") is selected.');
     // Ensure the none option is selected.
-    $this->assertNoRaw('This option is disabled because no modules that provide a text editor are currently enabled.', 'Description for select absent that tells users to install a text editor module.');
+    $this->assertSession()->responseNotContains('This option is disabled because no modules that provide a text editor are currently enabled.', 'Description for select absent that tells users to install a text editor module.');

     // Select the "Unicorn Editor" editor and click the "Configure" button.
     $edit = [
diff -u b/core/modules/editor/tests/src/Functional/EditorUploadImageScaleTest.php b/core/modules/editor/tests/src/Functional/EditorUploadImageScaleTest.php
--- b/core/modules/editor/tests/src/Functional/EditorUploadImageScaleTest.php
+++ b/core/modules/editor/tests/src/Functional/EditorUploadImageScaleTest.php
@@ -87,7 +87,7 @@
     list($uploaded_image_file_width, $uploaded_image_file_height) = $this->uploadImage($test_image->uri);
     $this->assertEqual($uploaded_image_file_width, $image_file_width);
     $this->assertEqual($uploaded_image_file_height, $image_file_height);
-    $this->assertNoRaw((string) new FormattableMarkup('The image was resized to fit within the maximum allowed dimensions of %dimensions pixels.', ['%dimensions' => $max_width . 'x' . $max_height]));
+    $this->assertSession()->responseNotContains((string) new FormattableMarkup('The image was resized to fit within the maximum allowed dimensions of %dimensions pixels.', ['%dimensions' => $max_width . 'x' . $max_height]));

     // Case 2: max width smaller than uploaded image: image scaled down.
     $test_image = $testing_image_list[1];
@@ -123,7 +123,7 @@
     list($uploaded_image_file_width, $uploaded_image_file_height) = $this->uploadImage($test_image->uri);
     $this->assertEqual($uploaded_image_file_width, $image_file_width);
     $this->assertEqual($uploaded_image_file_height, $image_file_height);
-    $this->assertNoRaw((string) new FormattableMarkup('The image was resized to fit within the maximum allowed dimensions of %dimensions pixels.', ['%dimensions' => $max_width . 'x' . $max_height]));
+    $this->assertSession()->responseNotContains((string) new FormattableMarkup('The image was resized to fit within the maximum allowed dimensions of %dimensions pixels.', ['%dimensions' => $max_width . 'x' . $max_height]));

     // Case 5: only max width dimension was provided and it was smaller than
     // uploaded image: image scaled down.
diff -u b/core/modules/field/tests/src/Functional/Boolean/BooleanFieldTest.php b/core/modules/field/tests/src/Functional/Boolean/BooleanFieldTest.php
--- b/core/modules/field/tests/src/Functional/Boolean/BooleanFieldTest.php
+++ b/core/modules/field/tests/src/Functional/Boolean/BooleanFieldTest.php
@@ -108,7 +108,7 @@
     $this->drupalGet('entity_test/add');
     $this->assertFieldByName("{$field_name}[value]", '', 'Widget found.');
     $this->assertText($this->field->label(), 'Uses field label by default.');
-    $this->assertNoRaw($on, 'Does not use the "On" label.');
+    $this->assertSession()->responseNotContains($on, 'Does not use the "On" label.');

     // Submit and ensure it is accepted.
     $edit = [
diff -u b/core/modules/field/tests/src/Functional/Number/NumberFieldTest.php b/core/modules/field/tests/src/Functional/Number/NumberFieldTest.php
--- b/core/modules/field/tests/src/Functional/Number/NumberFieldTest.php
+++ b/core/modules/field/tests/src/Functional/Number/NumberFieldTest.php
@@ -432,7 +432,7 @@
     ];
     $this->drupalPostForm($field_configuration_url, $edit, t('Save settings'));
     // Check if an error message is shown.
-    $this->assertNoRaw(t('%name is not a valid number.', ['%name' => t('Minimum')]), 'Saved ' . gettype($minimum_value) . '  value as minimal value on a ' . $field->getType() . ' field');
+    $this->assertSession()->responseNotContains(t('%name is not a valid number.', ['%name' => t('Minimum')]), 'Saved ' . gettype($minimum_value) . '  value as minimal value on a ' . $field->getType() . ' field');
     // Check if a success message is shown.
     $this->assertSession()->responseContains(t('Saved %label configuration.', ['%label' => $field->getLabel()]));
     // Check if the minimum value was actually set.