15 files declare their use of ContentEntityForm

AccountForm.php in core/modules/user/src/AccountForm.php
BlockContentForm.php in core/modules/block_content/src/BlockContentForm.php
BookOutlineForm.php in core/modules/book/src/Form/BookOutlineForm.php
CommentForm.php in core/modules/comment/src/CommentForm.php
EntityTestForm.php in core/modules/system/tests/modules/entity_test/src/EntityTestForm.php
FeedForm.php in core/modules/aggregator/src/FeedForm.php
MediaForm.php in core/modules/media/src/MediaForm.php
MenuLinkContentForm.php in core/modules/menu_link_content/src/Form/MenuLinkContentForm.php
MessageForm.php in core/modules/contact/src/MessageForm.php
NodeForm.php in core/modules/node/src/NodeForm.php
OverridesEntityForm.php in core/modules/layout_builder/src/Form/OverridesEntityForm.php
PathAliasForm.php in core/modules/path/src/PathAliasForm.php
ShortcutForm.php in core/modules/shortcut/src/ShortcutForm.php
TermForm.php in core/modules/taxonomy/src/TermForm.php
WorkspaceForm.php in core/modules/workspaces/src/Form/WorkspaceForm.php

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