Pressing sidebar button does not open or close skill menu, 'K' button works fine.
Also it has "(K)" in it's name, which factorio does by itself and even with actual (possibly changed) kaybinds.
Also K is already taken by factorio (uncouple the train).
Yeah, Alt+K is better, thank you! At least, i can't name a mod, that would conflict with it out of the box.
And just to check: sidebar button still doesn't work.