Horizontal mouse scroll doesn't work

Hello. I have the “horizontal mouse scroll” feature added here included in my sketch but it does not work on my Kubuntu Bionic system whether in KDE 5 or GTK 3 apps. I have confirmed that the horizontal scroll bar is visible and operable by the mouse but not by the MouseKey.

The vertical scrolling via MouseKey happens without any problem.

Is this perhaps another case of the host having problem with existence of two wheels which I seem to have read about on the bug tracker but re a different (Mac?) OS?

Any guidance to debug and solve would be much appreciated! :bouquet::apple::grapes:

Interesting… it used to work, but… it doesn’t now. I’ll look into it, thank you!

This is not a solution to this problem but I thought it worth mentioning that I just now accidentally found out that my frequently used vector graphics app Inkscape provides Shift + Wheel Up for scroll left and Shift + Wheel Down for scroll right, obviously since most pointing devices don’t provide horizontal wheels.

Just thought I’d record here that if this is to be implemented as a macro along the lines of this solution, it is better to use if (keyIsPressed(keyState)) rather than if (keyToggledOn(keyState)) normally used for macros.

Only then do we get a smooth experience comparable to scroll up/down with the unmodified keys Key_mouseScrollUp and Key_mouseScrollDn which give their effect as long as they are pressed and not once when toggled on ie initially pressed.