11 files declare their use of ReplaceCommand

AddFormBase.php in core/modules/media_library/src/Form/AddFormBase.php
AjaxCommandsTest.php in core/tests/Drupal/Tests/Core/Ajax/AjaxCommandsTest.php
BigPipe.php in core/modules/big_pipe/src/Render/BigPipe.php
ckeditor5.module in core/modules/ckeditor5/ckeditor5.module
LayoutRebuildTrait.php in core/modules/layout_builder/src/Controller/LayoutRebuildTrait.php
ManagedFile.php in core/modules/file/src/Element/ManagedFile.php
MediaLibraryWidget.php in core/modules/media_library/src/Plugin/Field/FieldWidget/MediaLibraryWidget.php
MediaTypeForm.php in core/modules/media/src/MediaTypeForm.php
ViewAjaxController.php in core/modules/views/src/Controller/ViewAjaxController.php
ViewEditForm.php in core/modules/views_ui/src/ViewEditForm.php
ViewsUIController.php in core/modules/views_ui/src/Controller/ViewsUIController.php

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