bug#32975: Emacs 26.1; GTK Warnings

[Robert Pluim]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Tjernlund <tjernlund@tjernlund.se>
>> Cc: 32975@debbugs.gnu.org
>> Date: Tue, 09 Oct 2018 20:33:45 +0200
>> 
>> > > > Do the problems go away if you disable the scroll bars?
>> > > 
>> > > The left side scroll bar?
>> > 
>> > All of them.
>> > 
>> > > Don't know howto do that ..
>> > 
>> > "M-x scroll-bar-mode RET" should toggle display of vertical scroll
>> > bars.  "M-x horizontal-scroll-bar-mode RET" should do the same with
>> > horizontal scroll bars.
>> 
>> They only happen one at startup, if if put in my .emacs:
>>    (scroll-bar-mode 0)
>> They are gone.
>
> Great, then my guess was correct.  These warnings come from
> xg_update_scrollbar_pos and from xg_finish_scroll_bar_creation.  Can
> some GTK expert try to find out why the scroll-bar widget seems to be
> reported as invalid)?  Robert, are you there?

I can't reproduce this under Gnome or KDE, with the same GTK version.
Which window manager/desktop environment is being used here?

Robert