9 classes are annotated with QueueWorker

AggregatorRefresh in core/modules/aggregator/src/Plugin/QueueWorker/AggregatorRefresh.php
Updates a feed's items.
CronQueueTestBrokenQueue in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestBrokenQueue.php
Plugin annotation @QueueWorker( id = "cron_queue_test_broken_queue", title = @Translation("Broken queue test"), cron = {"time" = 60} )
CronQueueTestDatabaseDelayException in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestDatabaseDelayException.php
A queue worker for testing cron exception handling.
CronQueueTestException in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestException.php
Plugin annotation @QueueWorker( id = "cron_queue_test_exception", title = @Translation("Exception test"), cron = {"time" = 1} )
CronQueueTestLeaseTime in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestLeaseTime.php
Plugin annotation @QueueWorker( id = "cron_queue_test_lease_time", title = @Translation("Lease time test"), cron = {"time" = 100} )
CronQueueTestMemoryDelayException in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestMemoryDelayException.php
A queue worker for testing cron exception handling.
CronQueueTestRequeueException in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestRequeueException.php
Plugin annotation @QueueWorker( id = "cron_queue_test_requeue_exception", title = @Translation("RequeueException test"), cron = {"time" = 60} )
LocaleTranslation in core/modules/locale/src/Plugin/QueueWorker/LocaleTranslation.php
Executes interface translation queue tasks.
ThumbnailDownloader in core/modules/media/src/Plugin/QueueWorker/ThumbnailDownloader.php
Process a queue of media items to fetch their thumbnails.

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