Memory full, fifo error

I also get this quite regularly now. My wife too, but much less often.
Anything I can do to help find the cause before doing a factory reset?
I am on 2.12.126, she is on 2.13 which are the same thing if I remember right.
I guess its about RAM?! How can I get Stats about that?

>require("Storage").getStats()
={ totalBytes: 8388608, freeBytes: 7335192, fileBytes: 499652, fileCount: 133,
  trashBytes: 553640, trashCount: 310 }

Current state:

• clock face is shown only partly (sometimes completely black screen) and doesn't change anymore
  
• Longpress (both reboot or just to watch-face) removes problem for some hours (time is shown correctly then, so something was still working in the background).
  
• Repeat
  
  

{Update] Don't know if that helps:
Got into that situation while connected in WebIDE. Saw whole screen full of

Execution Interrupted during event processing.
Execution Interrupted
Execution Interrupted during event processing.
Execution Interrupted
Execution Interrupted during event processing.
Execution Interrupted during event processing.
Execution Interrupted
Button held down - interrupt JS execution...
Button held down - interrupt JS execution...
Execution Interrupted during event processing.
Execution Interrupted during event processing.
>

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