98 files declare their use of Settings

ApcuBackendFactory.php in core/lib/Drupal/Core/Cache/ApcuBackendFactory.php
BootstrapConfigStorageFactory.php in core/lib/Drupal/Core/Config/BootstrapConfigStorageFactory.php
CacheFactory.php in core/lib/Drupal/Core/Cache/CacheFactory.php
CacheFactoryTest.php in core/tests/Drupal/Tests/Core/Cache/CacheFactoryTest.php
ChainedFastBackendFactory.php in core/lib/Drupal/Core/Cache/ChainedFastBackendFactory.php
ClientFactory.php in core/lib/Drupal/Core/Http/ClientFactory.php
ClientFactoryTest.php in core/tests/Drupal/Tests/Core/Http/ClientFactoryTest.php
ConfigEntityUpdaterTest.php in core/tests/Drupal/KernelTests/Core/Config/Entity/ConfigEntityUpdaterTest.php
ConfigFileContentTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigFileContentTest.php
ContextualController.php in core/modules/contextual/src/ContextualController.php
ContextualDynamicContextTest.php in core/modules/contextual/tests/src/Functional/ContextualDynamicContextTest.php
ContextualLinksPlaceholder.php in core/modules/contextual/src/Element/ContextualLinksPlaceholder.php
CoreServiceProvider.php in core/lib/Drupal/Core/CoreServiceProvider.php
CredentialForm.php in core/modules/migrate_drupal_ui/src/Form/CredentialForm.php
CsrfTokenGenerator.php in core/lib/Drupal/Core/Access/CsrfTokenGenerator.php
CsrfTokenGeneratorTest.php in core/tests/Drupal/Tests/Core/Access/CsrfTokenGeneratorTest.php
CustomStrings.php in core/lib/Drupal/Core/StringTranslation/Translator/CustomStrings.php
DatabaseBackendFactory.php in core/lib/Drupal/Core/Cache/DatabaseBackendFactory.php
DatabaseBackendFactoryTest.php in core/tests/Drupal/Tests/Core/Cache/DatabaseBackendFactoryTest.php
DiscoverServiceProvidersTest.php in core/tests/Drupal/Tests/Core/DrupalKernel/DiscoverServiceProvidersTest.php
DisplayBlockTest.php in core/modules/block/tests/src/Functional/Views/DisplayBlockTest.php
DrupalKernel.php in core/lib/Drupal/Core/DrupalKernel.php
DrupalKernelSiteTest.php in core/tests/Drupal/KernelTests/Core/DrupalKernel/DrupalKernelSiteTest.php
EntityAutocomplete.php in core/lib/Drupal/Core/Entity/Element/EntityAutocomplete.php
EntityAutocompleteTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityAutocompleteTest.php
ExcludedModulesEventSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ExcludedModulesEventSubscriber.php
ExtensionDiscovery.php in core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
FieldableEntityDefinitionUpdateTest.php in core/tests/Drupal/KernelTests/Core/Entity/FieldableEntityDefinitionUpdateTest.php
FileCopyTest.php in core/tests/Drupal/KernelTests/Core/File/FileCopyTest.php
FileMoveTest.php in core/tests/Drupal/KernelTests/Core/File/FileMoveTest.php
FileStorageFactory.php in core/lib/Drupal/Core/Config/FileStorageFactory.php
FileStorageFactoryTest.php in core/tests/Drupal/KernelTests/Core/Config/FileStorageFactoryTest.php
FileSystem.php in core/lib/Drupal/Core/File/FileSystem.php
FileSystemTest.php in core/tests/Drupal/Tests/Core/File/FileSystemTest.php
FinishResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
FormCache.php in core/lib/Drupal/Core/Form/FormCache.php
FormCacheTest.php in core/tests/Drupal/KernelTests/Core/Form/FormCacheTest.php
FunctionalTestSetupTrait.php in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
HtaccessTest.php in core/tests/Drupal/KernelTests/Core/File/HtaccessTest.php
HtaccessWriter.php in core/lib/Drupal/Core/File/HtaccessWriter.php
HtmlToTextTest.php in core/modules/system/tests/src/Functional/Mail/HtmlToTextTest.php
ImageStyle.php in core/modules/image/src/Entity/ImageStyle.php
ImageStyleDownloadController.php in core/modules/image/src/Controller/ImageStyleDownloadController.php
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
install.inc in core/includes/install.inc
API functions for installing modules and themes.
InstallCommand.php in core/lib/Drupal/Core/Command/InstallCommand.php
InstallerTestBase.php in core/tests/Drupal/FunctionalTests/Installer/InstallerTestBase.php
KernelTestBase.php in core/tests/Drupal/KernelTests/KernelTestBase.php
MailFormatHelper.php in core/lib/Drupal/Core/Mail/MailFormatHelper.php
MetadataBag.php in core/lib/Drupal/Core/Session/MetadataBag.php
MetadataBagTest.php in core/tests/Drupal/Tests/Core/Session/MetadataBagTest.php
MonkeysInTheControlRoom.php in core/modules/system/tests/modules/error_service_test/src/MonkeysInTheControlRoom.php
PageTitleTest.php in core/modules/system/tests/src/Functional/System/PageTitleTest.php
PermissionsHashGenerator.php in core/lib/Drupal/Core/Session/PermissionsHashGenerator.php
PermissionsHashGeneratorTest.php in core/tests/Drupal/Tests/Core/Session/PermissionsHashGeneratorTest.php
PhpMail.php in core/lib/Drupal/Core/Mail/Plugin/Mail/PhpMail.php
PhpStorageFactory.php in core/lib/Drupal/Core/PhpStorage/PhpStorageFactory.php
PhpStorageFactoryTest.php in core/modules/system/tests/src/Kernel/PhpStorage/PhpStorageFactoryTest.php
PrivateStream.php in core/lib/Drupal/Core/StreamWrapper/PrivateStream.php
PublicStream.php in core/lib/Drupal/Core/StreamWrapper/PublicStream.php
QueueFactory.php in core/lib/Drupal/Core/Queue/QueueFactory.php
rebuild.php in core/rebuild.php
Rebuilds all Drupal caches even when Drupal itself does not work.
ReplicaKillSwitch.php in core/lib/Drupal/Core/Database/ReplicaKillSwitch.php
ReplicaKillSwitchTest.php in core/tests/Drupal/KernelTests/Core/Database/ReplicaKillSwitchTest.php
ReverseProxyMiddleware.php in core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php
ReverseProxyMiddlewareTest.php in core/tests/Drupal/Tests/Core/StackMiddleware/ReverseProxyMiddlewareTest.php
SelectProfileForm.php in core/lib/Drupal/Core/Installer/Form/SelectProfileForm.php
ServerCommand.php in core/lib/Drupal/Core/Command/ServerCommand.php
ServiceProviderTestServiceProvider.php in core/modules/system/tests/modules/service_provider_test/src/ServiceProviderTestServiceProvider.php
SessionManagerTest.php in core/tests/Drupal/Tests/Core/Session/SessionManagerTest.php
SettingsRewriteTest.php in core/tests/Drupal/KernelTests/Core/Site/SettingsRewriteTest.php
SettingsTest.php in core/tests/Drupal/Tests/Core/Site/SettingsTest.php
SiteConfigureForm.php in core/lib/Drupal/Core/Installer/Form/SiteConfigureForm.php
SitesDirectoryHardeningTest.php in core/modules/system/tests/src/Functional/System/SitesDirectoryHardeningTest.php
SiteSettingsForm.php in core/lib/Drupal/Core/Installer/Form/SiteSettingsForm.php
SqlContentEntityStorageSchema.php in core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
SqlFieldableEntityTypeListenerTrait.php in core/lib/Drupal/Core/Entity/Sql/SqlFieldableEntityTypeListenerTrait.php
StreamWrapperManager.php in core/lib/Drupal/Core/StreamWrapper/StreamWrapperManager.php
StreamWrapperTest.php in core/tests/Drupal/KernelTests/Core/File/StreamWrapperTest.php
TestRunnerKernel.php in core/lib/Drupal/Core/Test/TestRunnerKernel.php
TestSiteUserLoginCommand.php in core/tests/Drupal/TestSite/Commands/TestSiteUserLoginCommand.php
theme.maintenance.inc in core/includes/theme.maintenance.inc
Theming for maintenance pages.
TranslationStringTest.php in core/tests/Drupal/KernelTests/Core/StringTranslation/TranslationStringTest.php
TwigEnvironmentTest.php in core/tests/Drupal/KernelTests/Core/Theme/TwigEnvironmentTest.php
TwigMarkupInterfaceTest.php in core/tests/Drupal/KernelTests/Core/Theme/TwigMarkupInterfaceTest.php
Contains \Drupal\KernelTests\Core\Theme\TwigMarkupInterfaceTest.
TwigSandboxPolicy.php in core/lib/Drupal/Core/Template/TwigSandboxPolicy.php
update.module in core/modules/update/update.module
Handles updates of Drupal core and contributed projects.
UpdateFetcher.php in core/modules/update/src/UpdateFetcher.php
UpdateFetcherTest.php in core/modules/update/tests/src/Unit/UpdateFetcherTest.php
UpdateKernel.php in core/lib/Drupal/Core/Update/UpdateKernel.php
UpdateManagerAccessCheck.php in core/modules/update/src/Access/UpdateManagerAccessCheck.php
UpdatePathTestBase.php in core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
UpdateRegistryTest.php in core/tests/Drupal/Tests/Core/Update/UpdateRegistryTest.php
user.module in core/modules/user/user.module
Enables the user registration and login system.
UserFloodSubscriber.php in core/modules/user/src/EventSubscriber/UserFloodSubscriber.php
UserRequestSubscriber.php in core/modules/user/src/EventSubscriber/UserRequestSubscriber.php
Yaml.php in core/lib/Drupal/Core/Serialization/Yaml.php
YamlTest.php in core/tests/Drupal/Tests/Core/Serialization/YamlTest.php

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