1459717 - Make trackpad scrolling on Linux behave more like native GTK3 apps

Status: NEW

(Core :: Panning and Zooming, defect, P3)

Description

[Botond Ballo [:botond]]

STR:
  1. Run Firefox and GEdit [1] on a Linux laptop.
  2. Compare two-finger scrolling in the two apps.

Expected results:
  Two-finger scrolling in Firefox is comparable to
  two-finger scrolling in GEdit.

Actual results:
  Two-finger scrolling in Firefox is considerably
  slower than two-finger scrolling in GEdit. In
  addition to being slower in terms of number of
  pixels scrolled, GEdit does momentum scrolling
  really well, while Firefox attempts to but does
  it poorly.

GEdit seems to be using GTK's GtkScrolledWindow widget [2] to implement scrolling. That makes use of additional GTK3 APIs that Firefox doesn't use (like gdk_event_get_scroll_deltas [3]) but could. It also implements its own momentum scrolling.

This bug tracks making Firefox's trackpad scrolling on Linux more like native GTK3 apps like GEdit.

[1] https://wiki.gnome.org/Apps/Gedit
[2] https://gitlab.gnome.org/GNOME/gtk/blob/gtk-3-22/gtk/gtkscrolledwindow.c
[3] https://gitlab.gnome.org/GNOME/gtk/blob/gtk-3-22/gtk/gtkscrolledwindow.c#L3463

Comment 2

[Nate Graham]

How about a hidden config option on the about:config page?

Comment 3

[Botond Ballo [:botond]]

(In reply to pointedstick from comment #2)
> How about a hidden config option on the about:config page?

This refers to a suggestion made in bug 1459506 comment 1. I reopened that bug to track implementing that suggestion.