Subject: bug#14324: 24.3; GTK scrollbar doesn't scroll proportionally when Line Wrapping is set to "Truncate Long Lines"

From: Lars Ingebrigtsen <[email-masked]>
Date: Thu, 03 Jun 2021 10:11:22 +0200

Eli Zaretskii <[email-masked]> writes:

> This bug is about Emacs getting "stuck" while scrolling, or scrolling
> erratically, not about miscalculation of the thumb size, right?

I interpreted "stuck" as "the scrollbar isn't moving" (or moving
erratically), but perhaps it's about really getting stuck?  Perhaps the
original bug reporter can clarify.

> I may be misremembering, but AFAIR that variable was introduced
> because some people actually _like_ the current default behavior wrt
> calculating the size of the scroll-bar thumb.

Sure, I can see somebody preferring the current behaviour (since it
reflects the actual buffer contents and not the visual contents).  But
in that case, both nil and t cases of `scroll-bar-adjust-thumb-portion'
should support visual/non-visual scroll bar lengths, perhaps?

(Because `scroll-bar-adjust-thumb-portion' is just about adjusting the
size so that you can always overscroll, according to the doc string.)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no