18 files declare their use of ConfigEntityUpdater

block_content.post_update.php in core/modules/block_content/block_content.post_update.php
Post update functions for Content Block.
ckeditor5.post_update.php in core/modules/ckeditor5/ckeditor5.post_update.php
Post update functions for CKEditor 5.
ConfigEntityUpdaterTest.php in core/tests/Drupal/KernelTests/Core/Config/Entity/ConfigEntityUpdaterTest.php
datetime_range.post_update.php in core/modules/datetime_range/datetime_range.post_update.php
Post-update functions for Datetime Range module.
editor.post_update.php in core/modules/editor/editor.post_update.php
Post update functions for Editor.
file.post_update.php in core/modules/file/file.post_update.php
Post update functions for File.
filter.post_update.php in core/modules/filter/filter.post_update.php
Post update functions for Filter.
help.post_update.php in core/modules/help/help.post_update.php
Post update functions for the Help module.
layout_builder.post_update.php in core/modules/layout_builder/layout_builder.post_update.php
Post update functions for Layout Builder.
media.post_update.php in core/modules/media/media.post_update.php
Post update functions for Media.
navigation.post_update.php in core/modules/navigation/navigation.post_update.php
Post update functions for the Navigation module.
node.post_update.php in core/modules/node/node.post_update.php
Post update functions for Node.
responsive_image.post_update.php in core/modules/responsive_image/responsive_image.post_update.php
Post update functions for Responsive Image.
system.post_update.php in core/modules/system/system.post_update.php
Post update functions for System.
taxonomy.post_update.php in core/modules/taxonomy/taxonomy.post_update.php
Post update functions for Taxonomy.
text.post_update.php in core/modules/text/text.post_update.php
Contains post update hooks for the text module.
user.post_update.php in core/modules/user/user.post_update.php
Post update functions for User module.
views.post_update.php in core/modules/views/views.post_update.php
Post update functions for Views.

Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.