8 files declare their use of LocalActionDefault

BlockContentAddLocalAction.php in core/modules/block_content/src/Plugin/Menu/LocalAction/BlockContentAddLocalAction.php
DisplayModeLocalAction.php in core/modules/field_ui/src/DisplayModeLocalAction.php
LocalActionDefaultTest.php in core/tests/Drupal/Tests/Core/Menu/LocalActionDefaultTest.php
MenuLinkAdd.php in core/modules/menu_ui/src/Plugin/Menu/LocalAction/MenuLinkAdd.php
TestLocalAction.php in core/modules/system/tests/modules/menu_test/src/Plugin/Menu/LocalAction/TestLocalAction.php
TestLocalAction4.php in core/modules/system/tests/modules/menu_test/src/Plugin/Menu/LocalAction/TestLocalAction4.php
TestLocalAction5.php in core/modules/system/tests/modules/menu_test/src/Plugin/Menu/LocalAction/TestLocalAction5.php
TestLocalActionWithConfig.php in core/modules/system/tests/modules/menu_test/src/Plugin/Menu/LocalAction/TestLocalActionWithConfig.php

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