Any expert on font-lock machinery able to provide some insight

[Harald Kirsch <pifpafpuf@gmx.de>]

Hi font-lock experts?

I am working on a font-lock function and see it called by the jit-lock
timer at weird times.

I see a normal font-lock function call after a change, for example when
inserting a character. But then I see

- calls when moving the cursor (no scroll)
- when setting the mark
- when moving the mouse into **another** frame
- when moving the mouse into yet **another** frame

I understand that when the function does not return

   (jit-lock-bounds beg . end)

jit-lock assumes the region was fontified just fine. For completeness I
also added the an explicit (jit-lock-bounds beg . end) return to my
font-lock function. Same behavior.

But it seems I am missing another channel of information which triggers
font-locking too often.

With describe-char I do see

There are text properties here:
   fontified            defer

not going away. Can this point to the problem?

Hints appreciated.

Harald


P.S.: I am not showing code on purpose as this would be a lot. I'd
rather just hear from anyone who might have had a similar issue to get
ideas where to look.