Comment 10 for bug 1697122

it's annoying for me too. The problem is that setting the envar just substitutes some problems with different ones:
- Without this envar set, there is no touchscreen scrolling, and touchpad scrolling goes three lines at a time rather than pixel-by-pixel
- With this envar set and a notification appears, touchpad scrolling is interrupted and mouse wheel scrolling stops working entirely until Firefox is de-focused and re-focused

The correct solution is to fix these bugs, not toggle between two broken states. Chromium has different scrolling bugs, BTW.