bug#42406: Mouse-wheel scrolling can be flickering

[Konrad Podczeck]

To clarify my observation:  If I comment out just the two calls to 
wset_update_mode_line that are in window_scroll_pixel_based, then the mouse 
wheel scrolling problem with multiple frames goes away, but the problem with 
scrolling via the scroll bars remains; if I comment out all five calls to 
wset_update_mode which are in window.c, then in addition the scroll-bar problem 
goes away (with multiple frames). I just wanted to know whether Martin has an 
idea which of the remaining three calls (when they are not out-commented) could 
be responsible for the scroll-bar problem.
 



> Am 16.12.2020 um 19:51 schrieb martin rudalics <rudalics@gmx.at>:
> 
> >> Then something else must come into play here.  I don't see where
> >> 'scroll-bar-toolkit-scroll' forces a mode line update.
> >
> > AFAIR, scroll-up does.
> 
> 'scroll-up' runs scroll_command and nothing else.  And if you mean the
> instances in window_scroll_pixel_based, then these are the ones Konrad
> removed in his Emacs.  Maybe the NS port does something completely
> different here ...
> 
> martin