WARN message "Stopped without executing or closing null"

About twice a day I get the following WARN message. Everything seems to be working fine but I just wondered what the reason for this is. Does anybody has a clue?

2023-10-14 11:29:41.117 [WARN ] [e.jetty.util.thread.QueuedThreadPool] - Stopped without executing or closing null

Thread: OH-thingHandler-x where x is constantly a different integer value