Linux Touchpad Smooth Scrolling

[tranquil-tr0]

Captchas

• [X] I have read the instructions.
• [X] I have searched existing issues and avoided creating duplicates.
• [X] I am not filing an enhancement request.

What happened?

In Zen Browser and Mozilla Firefox (no, this issue is not in both, paragraph 2 explains), scrolling on a touchpad is forced to be segmented, as would be expected behavior if the input device was a typical (not smooth scroll) mouse wheel. In Chromium browsers, this scrolling issue is not present (eg: scrolling is pixel-by-pixel at a normal speed in Brave Browser and Chrome).

However, in Mozilla Firefox, you can fix laptop smooth scrolling by passing MOZ_USE_XINPUT2=1 when launching firefox, and can be made persistent as a setting by running echo export MOZ_USE_XINPUT2=1 | sudo tee /etc/profile.d/use-xinput2.sh. As I understand it, zen browser is based on Firefox, so I assume that the issue is the same as the one there.

Reproducible?

• [X] I have checked that this issue cannot be reproduced on Mozilla Firefox.

Version

1.0.1-a.7

What platform are you seeing the problem on?

Linux

Relevant log output

No response

[linear[bot]]

ZEN-1935 Linux Touchpad Smooth Scrolling

[tranquil-tr0]

The issue is fixed in Wayland desktop compositor, and is limited to X11.

[mxmvncnt]

Maybe not fully related, but on Linux devices, the scroll speed on a touchpad under Wayland is very fast (This is a problem in upstream Firefox, I think it is caused by GTK3). To mitigate this, I have edited the values in about:config to the following:

• mousewheel.default.delta_multiplier_x to 20
• mousewheel.default.delta_multiplier_y to 20
• mousewheel.default.delta_multiplier_z to 20

But those settings break mousewheel scrolling by making it 5x slower, to fix this:

• mousewheel.min_line_scroll_amount to 300

To make the scrolling feel more natural, I also increase apz.fling_friction to 0.005

This would need to be applied only for Linux and Wayland environments, not sure how feasable this is.

[tranquil-tr0]

@mxmvncnt (edited to add @-ing) I am unable to verify whether what you said is true, since my delta multipliers all seem to be set to 100 and my scrolling isn't too fast, with the scrolling becoming very slow at 20 (on second thought, I've set mine to 70). Also, the issue might be unrelated, since I would assume that the issue is caused by strange touchpad recognition in Wayland (I could totally be wrong) or from some kind of failure to recognize input (which might then be related). P.S. Thanks for bringing up apz.fling_friction though, because that was my one issue with the browser after finally ditching X11 and the flatpak (since I initially didn't know how the portable package worked).

[RayZ3R0]

I think this is more of a linux issue, cuz I also had this problem in some apps with scrolling being weird. Is it alright now with what mxmvncnt suggested?

[tranquil-tr0]

I can't comment on mxmvcnt's solution, as I did not face the same issue. My solution to the original report was to move to Wayland, which isn't always possible but perhaps makes sense since in my experience the browser doesn't work great on older hardware (which would be a factor preventing on Wayland, it does for me) anyways (I have a roughly 14 year old desktop, on which Zen isn't exactly usable). Edit: Zen isn't "unusable" (on the older device) but just slower, which I expect anyways since Firefox for some reason runs roughly at 70% the speed of chromium, so I assume it is some kind of a Gecko issue.

[dosubot[bot]]

Hi, @tranquil-tr0. I'm Dosu, and I'm helping the desktop team manage their backlog. I'm marking this issue as stale.

Issue Summary:

• Problem with segmented touchpad scrolling in Zen Browser on Linux.
• Resolved by switching from X11 to Wayland, as confirmed by you.
• Suggested configuration adjustments for Wayland by user mxmvncnt.
• RayZ3R0 noted the issue might be related to Linux itself.

Next Steps:

• Is this issue still relevant to the latest version of the desktop repository? If so, please comment to keep the discussion open.
• Otherwise, the issue will be automatically closed in 7 days.

Thank you for your understanding and contribution!