23 files declare their use of SqlContentEntityStorage

CommentStorage.php in core/modules/comment/src/CommentStorage.php
contact_storage_test.install in core/modules/contact/tests/modules/contact_storage_test/contact_storage_test.install
Contains install and update hooks.
ContentTranslationTestBase.php in core/modules/content_translation/tests/src/Functional/ContentTranslationTestBase.php
DeprecatedEntityStorage.php in core/modules/system/tests/modules/entity_test_deprecated_storage/src/Storage/DeprecatedEntityStorage.php
EntityTestNoLoadStorage.php in core/modules/system/tests/modules/entity_test/src/EntityTestNoLoadStorage.php
EntityTestUpdateStorage.php in core/modules/system/tests/modules/entity_test_update/src/EntityTestUpdateStorage.php
FeedStorage.php in core/modules/aggregator/src/FeedStorage.php
FieldDataCountTest.php in core/modules/field/tests/src/Kernel/FieldDataCountTest.php
FileStorage.php in core/modules/file/src/FileStorage.php
ItemStorage.php in core/modules/aggregator/src/ItemStorage.php
MediaStorage.php in core/modules/media/src/MediaStorage.php
MenuLinkContentStorage.php in core/modules/menu_link_content/src/MenuLinkContentStorage.php
NodeStorage.php in core/modules/node/src/NodeStorage.php
PathAliasStorage.php in core/modules/path_alias/src/PathAliasStorage.php
SqlContentEntityStorageTest.php in core/tests/Drupal/Tests/Core/Entity/Sql/SqlContentEntityStorageTest.php
Contains \Drupal\Tests\Core\Entity\Sql\SqlContentEntityStorageTest.
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
taxonomy.module in core/modules/taxonomy/taxonomy.module
Enables the organization of content into categories.
TermStorage.php in core/modules/taxonomy/src/TermStorage.php
user.install in core/modules/user/user.install
Install, update and uninstall functions for the user module.
UserStorage.php in core/modules/user/src/UserStorage.php
views.views.inc in core/modules/views/views.views.inc
Provide views data that isn't tied to any other module.
ViewsEntitySchemaSubscriber.php in core/modules/views/src/EventSubscriber/ViewsEntitySchemaSubscriber.php
WorkspaceAssociation.php in core/modules/workspaces/src/WorkspaceAssociation.php

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