6 files declare their use of WebformManagedFileBase in Webform 6.x

RemotePostWebformHandler.php in src/Plugin/WebformHandler/RemotePostWebformHandler.php

WebformDevelSchema.php in modules/webform_devel/src/WebformDevelSchema.php

WebformSubmissionExportImportImporter.php in modules/webform_submission_export_import/src/WebformSubmissionExportImportImporter.php

WebformSubmissionStorage.php in src/WebformSubmissionStorage.php

WebformUiElementTypeFormBase.php in modules/webform_ui/src/Form/WebformUiElementTypeFormBase.php

webform_test.test_element_title_display.inc in tests/modules/webform_test/includes/webform_test.test_element_title_display.inc

Generate test elements title displays.