48 files declare their use of Attribute

ActiveLinkResponseFilterTest.php in core/tests/Drupal/Tests/Core/EventSubscriber/ActiveLinkResponseFilterTest.php
AttributeHelperTest.php in core/tests/Drupal/Tests/Core/Template/AttributeHelperTest.php
AttributesTest.php in core/tests/Drupal/Tests/Core/Common/AttributesTest.php
AttributeTest.php in core/tests/Drupal/Tests/Core/Template/AttributeTest.php
AttributeXss.php in core/modules/link/src/AttributeXss.php
claro.theme in core/themes/claro/claro.theme
Functions to support theming in the Claro theme.
ComponentElement.php in core/lib/Drupal/Core/Render/Element/ComponentElement.php
ComponentRenderTest.php in core/tests/Drupal/KernelTests/Components/ComponentRenderTest.php
ComponentValidatorTest.php in core/tests/Drupal/Tests/Core/Theme/Component/ComponentValidatorTest.php
ContextualLinksPlaceholder.php in core/modules/contextual/src/Element/ContextualLinksPlaceholder.php
DatePreprocess.php in core/lib/Drupal/Core/Datetime/DatePreprocess.php
DisplayBlockTest.php in core/modules/block/tests/src/Functional/Views/DisplayBlockTest.php
FieldPreprocess.php in core/lib/Drupal/Core/Field/FieldPreprocess.php
FileMediaFormatterBase.php in core/modules/file/src/Plugin/Field/FieldFormatter/FileMediaFormatterBase.php
FileThemeHooks.php in core/modules/file/src/Hook/FileThemeHooks.php
FilterThemeHooks.php in core/modules/filter/src/Hook/FilterThemeHooks.php
FormPreprocess.php in core/lib/Drupal/Core/Form/FormPreprocess.php
HtmlTag.php in core/lib/Drupal/Core/Render/Element/HtmlTag.php
Htmx.php in core/lib/Drupal/Core/Htmx/Htmx.php
HtmxUtilitiesTest.php in core/tests/Drupal/Tests/Core/Htmx/HtmxUtilitiesTest.php
Icon.php in core/lib/Drupal/Core/Render/Element/Icon.php
IconTest.php in core/tests/Drupal/Tests/Core/Theme/Icon/IconTest.php
LanguageThemeHooks.php in core/modules/language/src/Hook/LanguageThemeHooks.php
LayoutDiscoveryThemeHooks.php in core/modules/layout_discovery/src/Hook/LayoutDiscoveryThemeHooks.php
LinkGenerator.php in core/lib/Drupal/Core/Utility/LinkGenerator.php
MarkupNormalizerTest.php in core/modules/serialization/tests/src/Unit/Normalizer/MarkupNormalizerTest.php
MediaLibraryThemeHooks.php in core/modules/media_library/src/Hook/MediaLibraryThemeHooks.php
MediaThemeHooks.php in core/modules/media/src/Hook/MediaThemeHooks.php
MenuLinkTree.php in core/lib/Drupal/Core/Menu/MenuLinkTree.php
MenuLinkTreeTest.php in core/modules/system/tests/src/Unit/Menu/MenuLinkTreeTest.php
NodeThemeHooks.php in core/modules/node/src/Hook/NodeThemeHooks.php
olivero.theme in core/themes/olivero/olivero.theme
Functions to support theming in the Olivero theme.
PagerPreprocess.php in core/lib/Drupal/Core/Pager/PagerPreprocess.php
RendererTest.php in core/tests/Drupal/Tests/Core/Render/RendererTest.php
ResponsiveImageBuilder.php in core/modules/responsive_image/src/ResponsiveImageBuilder.php
SvgExtractor.php in core/lib/Drupal/Core/Theme/Plugin/IconExtractor/SvgExtractor.php
SvgExtractorTest.php in core/tests/Drupal/Tests/Core/Theme/Icon/Plugin/SvgExtractorTest.php
SystemAdminThemePreprocess.php in core/modules/system/src/Theme/SystemAdminThemePreprocess.php
ThemeManager.php in core/lib/Drupal/Core/Theme/ThemeManager.php
ThemePreprocess.php in core/lib/Drupal/Core/Theme/ThemePreprocess.php
ToolbarThemeHooks.php in core/modules/toolbar/src/Hook/ToolbarThemeHooks.php
TwigAttributesTest.php in core/tests/Drupal/KernelTests/Core/Theme/TwigAttributesTest.php
TwigExtensionTest.php in core/tests/Drupal/Tests/Core/Template/TwigExtensionTest.php
TwigSandboxTest.php in core/tests/Drupal/Tests/Core/Template/TwigSandboxTest.php
TwigThemeTestController.php in core/modules/system/tests/modules/twig_theme_test/src/TwigThemeTestController.php
UpdateThemeHooks.php in core/modules/update/src/Hook/UpdateThemeHooks.php
ViewsThemeHooks.php in core/modules/views/src/Hook/ViewsThemeHooks.php
ViewsUiThemeHooks.php in core/modules/views_ui/src/Hook/ViewsUiThemeHooks.php

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