bug#3956: Scroll bar thumb changes size when scrolling on macOS

[Stefan Kangas]

tags 3956 + notabug
close 3956
thanks

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Ville-Markus Yli-Suutala <villemarkus.ylisuutala@gmail.com>
>> Date: Sun, 22 Aug 2021 23:35:43 +0300
>> Cc: 3956@debbugs.gnu.org
>>
>> On Sun, Aug 22, 2021 at 9:06 AM Eli Zaretskii <eliz@gnu.org> wrote:
>> >
>> > > From: Ville-Markus Yli-Suutala <villemarkus.ylisuutala@gmail.com>
>> > > Date: Sat, 21 Aug 2021 23:40:48 +0300
>> > >
>> > > Height of the scrollbar thumb changes while scrolling on Windows too.
>> >
>> > That's how the scroll-bar thumb was designed to work in Emacs.
>>
>> By height changing I mean the tallness of the thumb, not its position
>> on the scrollbar.
>
> Yes, that's what I meant.
>
>> My display resolution is 1920 x 1080. If I start
>> Emacs with emacs -Q, click the maximize window button in the top right
>> corner, and go to the tutorial by pressing C-h t. The scrollbar thumb
>> is now 24 pixels tall. Now if I press C-v to scroll down, the
>> scrollbar thumb grows to be 42 pixels tall.
>>
>> Is it actually meant to work this way? GTK+ Emacs on my Debian machine
>> does not change the size of the scrollbar thumb as I scroll.
>
> The thumb reflects the size in characters, not in screen lines, so it
> cannot be constant as you scroll, especially if lines in the buffer
> differ a lot in their length.

Then I conclude that this works as designed on macOS, and I'm closing
this bug.

(That said, this is an unusual feature, IMHO.)