20 files declare their use of ExtensionLifecycle

ConfigImportAllTest.php in core/modules/config/tests/src/Functional/ConfigImportAllTest.php
DefaultConfigTest.php in core/tests/Drupal/KernelTests/Config/DefaultConfigTest.php
EntityFilteringThemeTest.php in core/modules/system/tests/src/Functional/Theme/EntityFilteringThemeTest.php
EntityResourceHalTestCoverageTest.php in core/modules/hal/tests/src/Kernel/EntityResource/EntityResourceHalTestCoverageTest.php
EntityResourceRestTestCoverageTest.php in core/modules/rest/tests/src/Kernel/EntityResource/EntityResourceRestTestCoverageTest.php
HelpController.php in core/modules/help/src/Controller/HelpController.php
HelpTopicsSyntaxTest.php in core/modules/help_topics/tests/src/Functional/HelpTopicsSyntaxTest.php
InfoParserUnitTest.php in core/tests/Drupal/Tests/Core/Extension/InfoParserUnitTest.php
InstallUninstallTest.php in core/modules/system/tests/src/Functional/Module/InstallUninstallTest.php
ModuleConfigureRouteTest.php in core/tests/Drupal/KernelTests/Core/Extension/ModuleConfigureRouteTest.php
ModulesListForm.php in core/modules/system/src/Form/ModulesListForm.php
ModulesListNonStableConfirmForm.php in core/modules/system/src/Form/ModulesListNonStableConfirmForm.php
ModulesUninstallForm.php in core/modules/system/src/Form/ModulesUninstallForm.php
ResolvedLibraryDefinitionsFilesMatchTest.php in core/tests/Drupal/KernelTests/Core/Asset/ResolvedLibraryDefinitionsFilesMatchTest.php
Stable9TemplateOverrideTest.php in core/tests/Drupal/KernelTests/Core/Theme/Stable9TemplateOverrideTest.php
StableLibraryOverrideTestBase.php in core/tests/Drupal/KernelTests/Core/Theme/StableLibraryOverrideTestBase.php
StableTemplateOverrideTest.php in core/tests/Drupal/KernelTests/Core/Theme/StableTemplateOverrideTest.php
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
SystemController.php in core/modules/system/src/Controller/SystemController.php
TestCoverageTest.php in core/modules/jsonapi/tests/src/Kernel/TestCoverageTest.php

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