35 files declare their use of Block

AreaEntityUITest.php in core/modules/views_ui/tests/src/Functional/AreaEntityUITest.php
AssertBlockAppearsTrait.php in core/modules/block/tests/src/Functional/AssertBlockAppearsTrait.php
block.module in core/modules/block/block.module
Controls the visual building blocks a page is constructed with.
BlockConfigSchemaTest.php in core/modules/block/tests/src/Kernel/BlockConfigSchemaTest.php
BlockContextMappingUpdateTest.php in core/modules/block/tests/src/Functional/Update/BlockContextMappingUpdateTest.php
BlockCreationTrait.php in core/modules/block/tests/src/Traits/BlockCreationTrait.php
BlockDependenciesTest.php in core/modules/views/tests/src/Kernel/Plugin/BlockDependenciesTest.php
BlockFormTest.php in core/modules/block/tests/src/Unit/BlockFormTest.php
BlockInvalidRegionTest.php in core/modules/block/tests/src/Functional/BlockInvalidRegionTest.php
BlockLanguageTest.php in core/modules/block/tests/src/Functional/BlockLanguageTest.php
BlockRebuildTest.php in core/modules/block/tests/src/Kernel/BlockRebuildTest.php
BlockResourceTestBase.php in core/modules/block/tests/src/Functional/Rest/BlockResourceTestBase.php
BlockStorageUnitTest.php in core/modules/block/tests/src/Kernel/BlockStorageUnitTest.php
BlockTemplateSuggestionsTest.php in core/modules/block/tests/src/Kernel/BlockTemplateSuggestionsTest.php
BlockTest.php in core/modules/block/tests/src/Functional/BlockTest.php
BlockTest.php in core/modules/jsonapi/tests/src/Functional/BlockTest.php
BlockViewBuilder.php in core/modules/block/src/BlockViewBuilder.php
BlockViewBuilderTest.php in core/modules/block/tests/src/Kernel/BlockViewBuilderTest.php
BreadcrumbTest.php in core/modules/system/tests/src/Functional/Menu/BreadcrumbTest.php
EntityCrudHookTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
ExposedFilterBlocksUpdateTest.php in core/modules/views/tests/src/Functional/Update/ExposedFilterBlocksUpdateTest.php
LanguageUILanguageNegotiationTest.php in core/modules/language/tests/src/Functional/LanguageUILanguageNegotiationTest.php
LocaleConfigManagerTest.php in core/modules/locale/tests/src/Kernel/LocaleConfigManagerTest.php
MenuBlockPostUpdateTest.php in core/modules/system/tests/src/Functional/Update/MenuBlockPostUpdateTest.php
MenuUiTest.php in core/modules/menu_ui/tests/src/Functional/MenuUiTest.php
MigrateBlockTest.php in core/modules/block/tests/src/Kernel/Migrate/d6/MigrateBlockTest.php
MigrateBlockTest.php in core/modules/block/tests/src/Kernel/Migrate/d7/MigrateBlockTest.php
NodeBlockFunctionalTest.php in core/modules/node/tests/src/Functional/NodeBlockFunctionalTest.php
OverriddenConfigurationTest.php in core/modules/settings_tray/tests/src/FunctionalJavascript/OverriddenConfigurationTest.php
SettingsTrayTest.php in core/modules/settings_tray/tests/src/Functional/SettingsTrayTest.php
SettingsTrayTestBase.php in core/modules/settings_tray/tests/src/FunctionalJavascript/SettingsTrayTestBase.php
settings_tray.module in core/modules/settings_tray/settings_tray.module
Allows configuring blocks and other configuration from the site front-end.
SystemMenuBlockTest.php in core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php
WebTestBase.php in core/modules/simpletest/src/WebTestBase.php
WhosOnlineBlockTest.php in core/modules/user/tests/src/Kernel/WhosOnlineBlockTest.php

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