diff --git a/core/lib/Drupal/Core/Routing/UrlGenerator.php b/core/lib/Drupal/Core/Routing/UrlGenerator.php
index 1b74c16..a9a9e1a 100644
--- a/core/lib/Drupal/Core/Routing/UrlGenerator.php
+++ b/core/lib/Drupal/Core/Routing/UrlGenerator.php
@@ -75,7 +75,7 @@ class UrlGenerator implements UrlGeneratorInterface {
    * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
    *   A request stack object.
    * @param string[] $filter_protocols
-   *   An array of protocols allowed for url generation.
+   *   An array of protocols allowed for URL generation.
    */
   public function __construct(RouteProviderInterface $provider, OutboundPathProcessorInterface $path_processor, OutboundRouteProcessorInterface $route_processor, RequestStack $request_stack, $filter_protocols) {
     $this->provider = $provider;
diff --git a/core/lib/Drupal/Core/Utility/UnroutedUrlAssembler.php b/core/lib/Drupal/Core/Utility/UnroutedUrlAssembler.php
index 8e591dc..550e1a4 100644
--- a/core/lib/Drupal/Core/Utility/UnroutedUrlAssembler.php
+++ b/core/lib/Drupal/Core/Utility/UnroutedUrlAssembler.php
@@ -43,7 +43,7 @@ class UnroutedUrlAssembler implements UnroutedUrlAssemblerInterface {
    * @param \Drupal\Core\PathProcessor\OutboundPathProcessorInterface $path_processor
    *   The output path processor.
    * @param string[] $filter_protocols
-   *   An array of protocols allowed for url generation.
+   *   An array of protocols allowed for URL generation.
    */
   public function __construct(RequestStack $request_stack, OutboundPathProcessorInterface $path_processor, $filter_protocols = []) {
     UrlHelper::setAllowedProtocols($filter_protocols ?: ['http', 'https']);
diff --git a/core/modules/migrate_drupal/migration_templates/d6_system_filter.yml b/core/modules/migrate_drupal/migration_templates/d6_system_filter.yml
deleted file mode 100644
index 739268d..0000000
--- a/core/modules/migrate_drupal/migration_templates/d6_system_filter.yml
+++ /dev/null
@@ -1,13 +0,0 @@
-id: d6_system_filter
-label: Drupal 6 filter configuration
-migration_tags:
-  - Drupal 6
-source:
-  plugin: variable
-  variables:
-    - filter_allowed_protocols
-process:
-  protocols: filter_allowed_protocols
-destination:
-  plugin: config
-  config_name: system.filter
diff --git a/core/modules/migrate_drupal/src/Tests/d6/MigrateSystemFilterTest.php b/core/modules/migrate_drupal/src/Tests/d6/MigrateSystemFilterTest.php
deleted file mode 100644
index 7249f46..0000000
--- a/core/modules/migrate_drupal/src/Tests/d6/MigrateSystemFilterTest.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\migrate_drupal\Tests\d6\MigrateSystemFilterTest.
- */
-
-namespace Drupal\migrate_drupal\Tests\d6;
-
-/**
- * Upgrade filter variables to system.*.yml.
- *
- * @group migrate_drupal
- */
-class MigrateSystemFilterTest extends MigrateDrupal6TestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-    $this->loadDumps(['Variable.php']);
-    $this->executeMigration('d6_system_filter');
-  }
-
-  /**
-   * Tests migration of system (filter) variables to system.filter.yml.
-   */
-  public function testSystemFilter() {
-    $filter_parameters = \Drupal::getContainer()->getParameter('filter_protocols');
-    $this->assertIdentical(array('http', 'https', 'ftp', 'news', 'nntp', 'tel', 'telnet', 'mailto', 'irc', 'ssh', 'sftp', 'webcal', 'rtsp'), $filter_parameters);
-  }
-
-}