Firefox touchpad pinch to zoom not working but touch pinch to zoom works on Linux

I'm having a weird issue with Firefox on Arch Linux running on a Lenovo Thinkpad L13 Yoga. I installed Firefox, and noticed that gestures on the touchpad or the touch screen do not work. I am using gnome, and all the gnome touchpad and touchscreen gestures work properly. I then added export MOZ_USE_XINPUT2=1 to profile.d and the touchscreen gestures started working on Firefox(scrolling and zooming) but the touchpad gestures still don't work. How do I fix this?

Solution 1:

Turns out MOZ_USE_XINPUT=1 was not alone enoguh to enable full libinput gestures, as Firefox also needed wayland to be enabled. Until now, Firefox was running through XWayland. Adding MOZ_ENABLE_WAYLAND=1 was not enough to change this, but once I added GDK_BACKEND=wayland, Firefox started using Wayland as the window protocol. All touch and touchpad gestures are now working.

However, the scrolling speed on the touchpad is still really fast, and I am going to try to see how I can fix that. If anyone knows how to change it, please comment it below.

Also, if anyone has an explaination for why Firefox behaves this way, and why this isn't default behaviour, please comment that down below as well.

Thank you to those who have helped.