I can't close a "verifying" core services UI agent window.
I have a little core services UI agent window, shown in the picture below, which is stuck, and which I can't close. Clicking on the 'X' to cancel doesn't do anything. Command-Option-Escape to force quit, doesn't show the window among the possibilities.
Is there a way to close this, without having to reboot my system?
MacBook Air 13″, macOS 12.6