25 files declare their use of Action

ActionAjaxTest.php in core/modules/action/tests/action_form_ajax_test/src/Plugin/Action/ActionAjaxTest.php
ActionManager.php in core/lib/Drupal/Core/Action/ActionManager.php
AddRoleUser.php in core/modules/user/src/Plugin/Action/AddRoleUser.php
AssignOwnerNode.php in core/modules/action/src/Plugin/Action/AssignOwnerNode.php
BatchUserAction.php in core/modules/views/tests/modules/user_batch_action_test/src/Plugin/Action/BatchUserAction.php
BlockUser.php in core/modules/user/src/Plugin/Action/BlockUser.php
CancelUser.php in core/modules/user/src/Plugin/Action/CancelUser.php
DeleteAction.php in core/lib/Drupal/Core/Action/Plugin/Action/DeleteAction.php
DemoteNode.php in core/modules/node/src/Plugin/Action/DemoteNode.php
EmailAction.php in core/lib/Drupal/Core/Action/Plugin/Action/EmailAction.php
GotoAction.php in core/lib/Drupal/Core/Action/Plugin/Action/GotoAction.php
MessageAction.php in core/lib/Drupal/Core/Action/Plugin/Action/MessageAction.php
NoType.php in core/modules/system/tests/modules/action_test/src/Plugin/Action/NoType.php
PromoteNode.php in core/modules/node/src/Plugin/Action/PromoteNode.php
PublishAction.php in core/lib/Drupal/Core/Action/Plugin/Action/PublishAction.php
RemoveRoleUser.php in core/modules/user/src/Plugin/Action/RemoveRoleUser.php
SaveAction.php in core/lib/Drupal/Core/Action/Plugin/Action/SaveAction.php
SaveEntity.php in core/modules/system/tests/modules/action_test/src/Plugin/Action/SaveEntity.php
StickyNode.php in core/modules/node/src/Plugin/Action/StickyNode.php
TestAction.php in core/modules/views/tests/modules/action_bulk_test/src/Plugin/Action/TestAction.php
UnblockUser.php in core/modules/user/src/Plugin/Action/UnblockUser.php
UnpublishAction.php in core/lib/Drupal/Core/Action/Plugin/Action/UnpublishAction.php
UnpublishByKeywordComment.php in core/modules/action/src/Plugin/Action/UnpublishByKeywordComment.php
UnpublishByKeywordNode.php in core/modules/action/src/Plugin/Action/UnpublishByKeywordNode.php
UnstickyNode.php in core/modules/node/src/Plugin/Action/UnstickyNode.php

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