Subject: bug#35246: 26.2; Mouse wheel scrolling in GTK build sometimes scrolls the entire buffer

From: Stefan Kangas <[email-masked]>
Date: Wed, 2 Sep 2020 17:32:24 -0400

Alex Gramiak <[email-masked]> writes:

> I just got another issue, and this time:
>
> 1) Busy cursor briefly appeared after several seconds of a
> non-responsive Emacs.
>
> 2) Scrolling occurred right after with a seemingly normal scrolling
> distance.

Here's an idea:

Do you see this only if you scroll while Emacs is busy?  Or do you see
this even without that precondition?

FWIW, I can reproduce the jumping action here with the following steps:

1. <go to the beginning some long buffer>
2. M-! sleep 2 RET
3. <scroll on the mouse wheel a lot>

Also, do you have `pixel-scroll-mode' enabled?