It would be nice if this mod added a control option for switching the hotbar slot left or right in addition to the default scrolling up/down, one use case for this is being able to use the forward/backward buttons on your mouse to change the held item slot, perhaps this could be the default when the mod is installed, as it feels like something that should really be in the vanilla game. Thank you

I added this functionality in my fork. Either wait for @Siphalor to publish it. Or compile it yourself.