124 files declare their use of Settings

ApcuBackendFactory.php in core/lib/Drupal/Core/Cache/ApcuBackendFactory.php
authorize.php in core/authorize.php
Administrative script for running authorized file operations.
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
ConfigImportForm.php in core/modules/config/src/Form/ConfigImportForm.php
ConfigImportUploadTest.php in core/modules/config/tests/src/Functional/ConfigImportUploadTest.php
ConfigInstallWebTest.php in core/modules/config/tests/src/Functional/ConfigInstallWebTest.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
db-tools.php in core/scripts/db-tools.php
A command line application to import a database generation script.
DbUpdateAccessCheck.php in core/modules/system/src/Access/DbUpdateAccessCheck.php
DbUpdateController.php in core/modules/system/src/Controller/DbUpdateController.php
DbUpdateNegotiator.php in core/modules/system/src/Theme/DbUpdateNegotiator.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
dump-database-d8-mysql.php in core/scripts/dump-database-d8-mysql.php
A command line application to dump a database to a generation script.
EntityAutocomplete.php in core/lib/Drupal/Core/Entity/Element/EntityAutocomplete.php
EntityAutocompleteController.php in core/modules/system/src/Controller/EntityAutocompleteController.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
FieldImportCreateTest.php in core/modules/field/tests/src/Kernel/FieldImportCreateTest.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
generate-proxy-class.php in core/scripts/generate-proxy-class.php
A script to generate proxy classes for lazy services.
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
IFrameUrlHelper.php in core/modules/media/src/IFrameUrlHelper.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
LanguageNegotiator.php in core/modules/language/src/LanguageNegotiator.php
MailFormatHelper.php in core/lib/Drupal/Core/Mail/MailFormatHelper.php
ManagedFile.php in core/modules/file/src/Element/ManagedFile.php
MediaLibraryState.php in core/modules/media_library/src/MediaLibraryState.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
NodeImportCreateTest.php in core/modules/node/tests/src/Kernel/Config/NodeImportCreateTest.php
NodeMigrateType.php in core/modules/migrate_drupal/src/NodeMigrateType.php
PageCache.php in core/modules/page_cache/src/StackMiddleware/PageCache.php
PageCacheTest.php in core/modules/page_cache/tests/src/Functional/PageCacheTest.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
SecurityAdvisoriesFetcher.php in core/modules/system/src/SecurityAdvisories/SecurityAdvisoriesFetcher.php
SelectionTest.php in core/modules/field/tests/src/Functional/EntityReference/Views/SelectionTest.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
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
system.module in core/modules/system/system.module
Configuration system that lets administrators modify the workings of the site.
system.post_update.php in core/modules/system/system.post_update.php
Post update functions for System.
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
WorkspaceManager.php in core/modules/workspaces/src/WorkspaceManager.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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