Scrolling in chromium based applications not working

[meir]

There has been a merge request for this before but that code has changed later on: #67
It seems to only affect chromium based programs (Discord and Spotify for example)

OS: NixOS 25.05 (unstable)
WM: Hyprland (0.47.0)
VR/HW: SteamVR + Valve Index
Version: v0.6

[meir]

Quickly tested it out with the changes from the PR, they do seem to still work however the mouse cannot be moved during it and hovering over with your other hand will stop the scrolling

[olekolek1000]

Yes, the mouse movement pause is an intended behavior. Scrolling should work just fine on the latest main branch. However, the second hand causing scrolling to stop is likely due to its update of the mouse position, which can interrupt scrolling in Chromium-based apps.

[meir]

Scrolling does not work for me on v0.6 or the main branch either, however when i reintroduce the changed from the PR, then it does work.

[galister]

@meir what refresh rate is your monitor that the electron app is running on?

[meir]

The monitor its on is running on 60hz i believe

[galister]

The problem with electron apps is that if they receive a scroll event on the same frame as they receive a pointer move event, the move event will be prioritized and the scroll event will be ignored.

For some reason, any other app can handle move and scroll at the same time.

What old wlx used to do is to simply not move the mouse while the user held the scroll binding.

We replaced this behavior with one where we alter the events; on frames where a scroll event needs to be sent, a move event will not be sent. The move event will be sent on the next frame instead.

The potential problem is that if the headset (and thus wlx) is running at 120hz and the monitor is running at 60hz, then the app will receive 2 frames worth of events from wlx within the same frame, basically cancelling out the altered packets.

I don't have any electron-based app to test with, but I would expect it to work well with a higher refresh rate monitor, or a lower refresh rate setting of the hmd.

The ideal solution would be to make it respect the display's refresh rate.

[galister]

alternatively, you can try setting the following via conf.d:

mouse_move_interval_ms: 33

[Anti-Apple4life]

I set mouse_move_interval_ms: 33 in a conf.d file, and it did not fix the issue. The mouse was a bit laggier though.