30 files declare their use of Event in Drupal 10

AccountSetEvent.php in core/lib/Drupal/Core/Session/AccountSetEvent.php

BlockContentGetDependencyEvent.php in core/modules/block_content/src/Event/BlockContentGetDependencyEvent.php

ConfigCollectionInfo.php in core/lib/Drupal/Core/Config/ConfigCollectionInfo.php

ConfigCrudEvent.php in core/lib/Drupal/Core/Config/ConfigCrudEvent.php

ConfigImporterEvent.php in core/lib/Drupal/Core/Config/ConfigImporterEvent.php

ConfigMapperPopulateEvent.php in core/modules/config_translation/src/Event/ConfigMapperPopulateEvent.php

ConfigModuleOverridesEvent.php in core/lib/Drupal/Core/Config/ConfigModuleOverridesEvent.php

ContainerAwareEventDispatcherTest.php in core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php

DrupalKernel.php in core/lib/Drupal/Core/DrupalKernel.php

EntityTypeEvent.php in core/lib/Drupal/Core/Entity/EntityTypeEvent.php

EventBase.php in core/modules/migrate/src/Event/EventBase.php

FieldStorageDefinitionEvent.php in core/lib/Drupal/Core/Field/FieldStorageDefinitionEvent.php

FileUploadSanitizeNameEvent.php in core/lib/Drupal/Core/File/Event/FileUploadSanitizeNameEvent.php

LanguageConfigOverrideCrudEvent.php in core/modules/language/src/Config/LanguageConfigOverrideCrudEvent.php

LocaleEvent.php in core/modules/locale/src/LocaleEvent.php

MigrateIdMapMessageEvent.php in core/modules/migrate/src/Event/MigrateIdMapMessageEvent.php

MigrateMapDeleteEvent.php in core/modules/migrate/src/Event/MigrateMapDeleteEvent.php

MigrateMapSaveEvent.php in core/modules/migrate/src/Event/MigrateMapSaveEvent.php

MigrateRollbackEvent.php in core/modules/migrate/src/Event/MigrateRollbackEvent.php

MigrateRowDeleteEvent.php in core/modules/migrate/src/Event/MigrateRowDeleteEvent.php

MissingContentEvent.php in core/lib/Drupal/Core/Config/Importer/MissingContentEvent.php

PageDisplayVariantSelectionEvent.php in core/lib/Drupal/Core/Render/PageDisplayVariantSelectionEvent.php

PrepareLayoutEvent.php in core/modules/layout_builder/src/Event/PrepareLayoutEvent.php

ResourceTypeBuildEvent.php in core/modules/jsonapi/src/ResourceType/ResourceTypeBuildEvent.php

RouteBuilder.php in core/lib/Drupal/Core/Routing/RouteBuilder.php

RouteBuildEvent.php in core/lib/Drupal/Core/Routing/RouteBuildEvent.php

RoutePreloaderTest.php in core/tests/Drupal/Tests/Core/Routing/RoutePreloaderTest.php

SectionComponentBuildRenderArrayEvent.php in core/modules/layout_builder/src/Event/SectionComponentBuildRenderArrayEvent.php

StorageTransformEvent.php in core/lib/Drupal/Core/Config/StorageTransformEvent.php

UserFloodEvent.php in core/modules/user/src/Event/UserFloodEvent.php