Issue with "sse events"

Every now and then I have literally hundreds of these log entries. Looks like they are blocking the openhab Server when they occur.
I am on Openhabian 3.2.0 M1, running on a Raspi4.

Anybody an idea what can cause this?

2021-09-05 18:22:09.732 [WARN ] [pache.cxf.jaxrs.sse.SseEventSinkImpl] - There are still SSE events the queue which may not be delivered (closing now)

I have the suspicion that this issue is related to habpanel and/or habpanelviewer.

I run into this problem at least once a day. It always happens when habpanelviewer is moved to the foreground / screen is turned on.

Any clue somebody?