1846180 - Scrolling senstivity changed on latest nightly

Status: UNCONFIRMED

(Core :: Widget: Gtk, defect)

Description

[nicopwn]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/117.0

Steps to reproduce:

On archlinux, KDE Wayland, firefox nightly's scrolling sensitivity changed(reduced to about 1/2). It was "normal" up to version 2023-07-28-17-48-24. Version 2023-07-28-21-29-03 is the first to have this issue.

Actual results:

Scrolling sensitivity is noticeably lower than stable.

Expected results:

Scrolling sensitivity is the same as stable.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Gtk' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Botond Ballo [:botond]]

This change is deliberate, as discussed in bug 1753033. You can restore the previous level of sensitivity by setting the pref apz.gtk.pangesture.delta_mode to 0 in about:config.

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

:ren, since you are the author of the regressor, bug 1753033, could you take a look?

For more information, please visit BugBot documentation.

Comment 4

[Botond Ballo [:botond]]

(Moving bug 1753033 to the "See Also" field as this is its intended effect.)

Comment 5

[nicopwn]

I opened the same text file on vscode, chrome, brave, and kate, and noted how much distance is required to cover the whole file. They were all similar, and I had to set apz.gtk.pangesture.delta_mode=160 to make firefox roughly match it.

I think it's pretty clear that gnome web is the outlier here, and I think regardless of the scroll mode, firefox's default behavior should match the majority of apps.

I suggest either apz.gtk.pangesture.delta_mode=1 OR apz.gtk.pangesture.delta_mode=2, apz.gtk.pangesture.delta_mode=160(or whatever value actually matches most apps) as the default, and adding a setting to adjust scroll speed in about:preferences to make the setting easier to adjust for those who want to.

Comment 6

[Emilio Cobos Álvarez [:emilio]]

delta_mode is a tri-state, 1 and 160 behave the same.

Comment 7

[Emilio Cobos Álvarez [:emilio]]

So I took a look and:

• gedit matches our previous behavior (delta_mode=1), amount we scroll depends on viewport size.
• gnome-builder has way slower scroll sensitivity than us either before or after.
• kate seems to use a bigger scroll step, but independent of window size (so something more similar to delta_mode=2, pixel_delta_mode_multiplier=50).

So I think if we change the defaults, we should consider bumping a bit the delta_mode_multiplier but probably not more than that.

Comment 8

[Botond Ballo [:botond]]

(In reply to Emilio Cobos Álvarez (:emilio) from comment #6)

delta_mode is a tri-state, 1 and 160 behave the same.

I suspect @nicopwn meant to write pixel_delta_mode_multiplier=160, i.e. on their machine, with delta_mode set to pixel (2), the multiplier had to be increased to 160 (4x its current value of 40) to get the scrolling to be as fast as some other apps.

Since you both tested Kate, and you came up with pixel_delta_mode_multiplier=50, I wonder if that means there is some other setting that differs between your machines that can affect this.

Comment 9

[Botond Ballo [:botond]]

FWIW, for me, the scrolling speed of a text file in Kate and Firefox Nightly are pretty similar with the current default settings (pixel_delta_mode_multiplier=40); there definitely isn't a 4x or even 2x difference.