12 files declare their use of AttachedAssetsInterface

AssetControllerBase.php in core/modules/system/src/Controller/AssetControllerBase.php
AssetResolverTest.php in core/tests/Drupal/Tests/Core/Asset/AssetResolverTest.php
BigPipe.php in core/modules/big_pipe/src/Render/BigPipe.php
Ckeditor5Hooks.php in core/modules/ckeditor5/src/Hook/Ckeditor5Hooks.php
CommonTestHooks.php in core/modules/system/tests/modules/common_test/src/Hook/CommonTestHooks.php
CssAssetController.php in core/modules/system/src/Controller/CssAssetController.php
HtmlResponseAttachmentsProcessor.php in core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
JsAssetController.php in core/modules/system/src/Controller/JsAssetController.php
LocaleHooks.php in core/modules/locale/src/Hook/LocaleHooks.php
SettingsTrayHooks.php in core/modules/settings_tray/src/Hook/SettingsTrayHooks.php
SystemHooks.php in core/modules/system/src/Hook/SystemHooks.php
UserHooks.php in core/modules/user/src/Hook/UserHooks.php

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