34 files declare their use of ControllerBase

AggregatorController.php in core/modules/aggregator/src/Controller/AggregatorController.php
AggregatorTestRssController.php in core/modules/aggregator/tests/modules/aggregator_test/src/Controller/AggregatorTestRssController.php
BlockAddController.php in core/modules/block/src/Controller/BlockAddController.php
BlockController.php in core/modules/block/src/Controller/BlockController.php
BlockLibraryController.php in core/modules/block/src/Controller/BlockLibraryController.php
CommentController.php in core/modules/comment/src/Controller/CommentController.php
CommentTestController.php in core/modules/comment/tests/modules/comment_test/src/Controller/CommentTestController.php
EditorController.php in core/modules/editor/src/EditorController.php
EntityListController.php in core/lib/Drupal/Core/Entity/Controller/EntityListController.php
ErrorTestController.php in core/modules/system/tests/modules/error_test/src/Controller/ErrorTestController.php
FormTestController.php in core/modules/system/tests/modules/form_test/src/Controller/FormTestController.php
JqueryUiTestAssetsController.php in core/modules/system/tests/modules/jqueryui_library_assets_test/src/Controller/JqueryUiTestAssetsController.php
JsCookieTestController.php in core/modules/system/tests/modules/js_cookie_test/src/Controller/JsCookieTestController.php
LonelyMonkeyController.php in core/modules/system/tests/modules/error_service_test/src/Controller/LonelyMonkeyController.php
ManyAssetsTestController.php in core/modules/system/tests/modules/many_assets_test/src/Controller/ManyAssetsTestController.php
MigrateController.php in core/modules/migrate_drupal_ui/src/Controller/MigrateController.php
PagerTestController.php in core/modules/system/tests/modules/pager_test/src/Controller/PagerTestController.php
QuickEditController.php in core/modules/quickedit/src/QuickEditController.php
QuickEditImageController.php in core/modules/image/src/Controller/QuickEditImageController.php
QuickEditImageController.php in core/modules/quickedit/src/Controller/QuickEditImageController.php
RenderArrayNonHtmlSubscriberTestController.php in core/modules/system/tests/modules/render_array_non_html_subscriber_test/src/RenderArrayNonHtmlSubscriberTestController.php
SessionTestController.php in core/modules/system/tests/modules/session_test/src/Controller/SessionTestController.php
TabbingManagerTestController.php in core/modules/system/tests/modules/tabbingmanager_test/src/Controller/TabbingManagerTestController.php
TaxonomyController.php in core/modules/taxonomy/src/Controller/TaxonomyController.php
TestController.php in core/modules/system/tests/modules/csrf_race_test/src/Controller/TestController.php
TestMultipleFormController.php in core/modules/block/tests/modules/block_test/src/Controller/TestMultipleFormController.php
ThemeTestController.php in core/modules/system/tests/modules/theme_legacy_test/src/ThemeTestController.php
ToolbarController.php in core/modules/toolbar/src/Controller/ToolbarController.php
UpdateController.php in core/modules/update/src/Controller/UpdateController.php
UpdateScriptTestController.php in core/modules/system/tests/modules/update_script_test/src/Controller/UpdateScriptTestController.php
UpdateTestController.php in core/modules/update/tests/modules/update_test/src/Controller/UpdateTestController.php
UserAuthenticationController.php in core/modules/user/src/Controller/UserAuthenticationController.php
UserController.php in core/modules/user/src/Controller/UserController.php
ViewsUIController.php in core/modules/views_ui/src/Controller/ViewsUIController.php

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