8 files declare their use of ConfigurableActionBase

ActionAjaxTest.php in core/modules/action/tests/action_form_ajax_test/src/Plugin/Action/ActionAjaxTest.php
AssignOwnerNode.php in core/modules/node/src/Plugin/Action/AssignOwnerNode.php
ChangeUserRoleBase.php in core/modules/user/src/Plugin/Action/ChangeUserRoleBase.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
UnpublishByKeywordComment.php in core/modules/comment/src/Plugin/Action/UnpublishByKeywordComment.php
UnpublishByKeywordNode.php in core/modules/node/src/Plugin/Action/UnpublishByKeywordNode.php

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