I think I figured out the problem… It has onboard memory for one profile, whichever is selected in the UI. My default profile has a bunch of buttons mapped that do not register as key presses when booted into Linux, so input remapper doesn’t pick those up when the mouse button is pressed.

My solution was to create a profile that had all of the side buttons mapped as regular keyboard keys, and activate that profile before booting into Linux.

libratbag and Piper don’t support my mouse (or any razer mice), unfortunately. I’ve also tried input remapper… couldn’t get it working right on Bazzite, but maybe I was just doing something very wrong. Will give it another try!

I have. That allows for control of lighting, but doesn’t do key mapping/profiles.

The only thing stopping me is I can’t figure out how to remap the side buttons on my razer MMO mouse in Linux.