23 files declare their use of MenuLinkContent

ConfigAccessTest.php in core/modules/settings_tray/tests/src/FunctionalJavascript/ConfigAccessTest.php
DisplayPathTest.php in core/modules/views_ui/tests/src/Functional/DisplayPathTest.php
LanguageSwitchingTest.php in core/modules/language/tests/src/Functional/LanguageSwitchingTest.php
MenuCacheTagsTest.php in core/modules/menu_ui/tests/src/Functional/MenuCacheTagsTest.php
MenuLinkContentCacheabilityBubblingTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentCacheabilityBubblingTest.php
MenuLinkContentDeleteFormTest.php in core/modules/menu_link_content/tests/src/Functional/MenuLinkContentDeleteFormTest.php
MenuLinkContentDeriverTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentDeriverTest.php
MenuLinkContentFormTest.php in core/modules/menu_link_content/tests/src/Functional/MenuLinkContentFormTest.php
MenuLinkContentResourceTestBase.php in core/modules/menu_link_content/tests/src/Functional/Rest/MenuLinkContentResourceTestBase.php
MenuLinkContentTest.php in core/modules/jsonapi/tests/src/Functional/MenuLinkContentTest.php
MenuLinkContentTranslationUITest.php in core/modules/menu_link_content/tests/src/Functional/MenuLinkContentTranslationUITest.php
MenuLinkSecurityTest.php in core/modules/system/tests/src/Functional/Menu/MenuLinkSecurityTest.php
MenuLinksTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php
MenuLinkTest.php in core/modules/views/tests/src/Functional/Plugin/MenuLinkTest.php
MenuUiNodeTest.php in core/modules/menu_ui/tests/src/Functional/MenuUiNodeTest.php
MenuUiTest.php in core/modules/menu_ui/tests/src/Functional/MenuUiTest.php
menu_ui.module in core/modules/menu_ui/menu_ui.module
Allows administrators to customize the site's navigation menus.
MigrateMenuLinkTest.php in core/modules/menu_link_content/tests/src/Kernel/Migrate/d7/MigrateMenuLinkTest.php
MigrateMenuLinkTest.php in core/modules/menu_link_content/tests/src/Kernel/Migrate/d6/MigrateMenuLinkTest.php
MigrateMenuLinkTranslationTest.php in core/modules/menu_link_content/tests/src/Kernel/Migrate/d6/MigrateMenuLinkTranslationTest.php
OverriddenConfigurationTest.php in core/modules/settings_tray/tests/src/FunctionalJavascript/OverriddenConfigurationTest.php
PathAliasMenuLinkContentTest.php in core/modules/menu_link_content/tests/src/Kernel/PathAliasMenuLinkContentTest.php
SessionTest.php in core/tests/Drupal/FunctionalJavascriptTests/Core/Session/SessionTest.php

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