32 files declare their use of AjaxResponse

AjaxCssForm.php in core/modules/ckeditor/tests/modules/src/Form/AjaxCssForm.php
AjaxRenderer.php in core/lib/Drupal/Core/Render/MainContent/AjaxRenderer.php
AjaxResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/AjaxResponseSubscriber.php
AjaxResponseTest.php in core/tests/Drupal/Tests/Core/Ajax/AjaxResponseTest.php
AjaxTestController.php in core/modules/system/tests/modules/ajax_test/src/Controller/AjaxTestController.php
AjaxTestDialogForm.php in core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestDialogForm.php
AjaxTestFocusFirstForm.php in core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestFocusFirstForm.php
AjaxTestFormPromise.php in core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestFormPromise.php
AjaxTestImageEffect.php in core/modules/image/tests/modules/image_module_test/src/Plugin/ImageEffect/AjaxTestImageEffect.php
AjaxTestMessageCommandForm.php in core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestMessageCommandForm.php
BigPipe.php in core/modules/big_pipe/src/Render/BigPipe.php
BigPipeResponseAttachmentsProcessorTest.php in core/modules/big_pipe/tests/src/Unit/Render/BigPipeResponseAttachmentsProcessorTest.php
Callbacks.php in core/modules/system/tests/modules/ajax_forms_test/src/Callbacks.php
CommandsTest.php in core/tests/Drupal/KernelTests/Core/Ajax/CommandsTest.php
DialogRenderer.php in core/lib/Drupal/Core/Render/MainContent/DialogRenderer.php
DummyAjaxWidget.php in core/modules/image/tests/modules/image_module_test/src/Plugin/Field/FieldWidget/DummyAjaxWidget.php
EarlyRenderingControllerWrapperSubscriber.php in core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php
EarlyRenderingTestController.php in core/modules/system/tests/modules/early_rendering_controller_test/src/EarlyRenderingTestController.php
EditorImageDialog.php in core/modules/editor/src/Form/EditorImageDialog.php
EditorLinkDialog.php in core/modules/editor/src/Form/EditorLinkDialog.php
FormAjaxResponseBuilder.php in core/lib/Drupal/Core/Form/FormAjaxResponseBuilder.php
FormAjaxResponseBuilderTest.php in core/tests/Drupal/Tests/Core/Form/FormAjaxResponseBuilderTest.php
FormAjaxSubscriber.php in core/lib/Drupal/Core/Form/EventSubscriber/FormAjaxSubscriber.php
JsAjaxTestForm.php in core/modules/system/tests/modules/js_ajax_test/src/Form/JsAjaxTestForm.php
ModalRenderer.php in core/lib/Drupal/Core/Render/MainContent/ModalRenderer.php
OffCanvasRenderer.php in core/lib/Drupal/Core/Render/MainContent/OffCanvasRenderer.php
QuickEditController.php in core/modules/quickedit/src/QuickEditController.php
ToolbarController.php in core/modules/toolbar/src/Controller/ToolbarController.php
ViewEditForm.php in core/modules/views_ui/src/ViewEditForm.php
ViewsFormBase.php in core/modules/views_ui/src/Form/Ajax/ViewsFormBase.php
ViewsUIController.php in core/modules/views_ui/src/Controller/ViewsUIController.php
WideModalRenderer.php in core/modules/system/tests/modules/dialog_renderer_test/src/Render/MainContent/WideModalRenderer.php

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