This has been bugging me. For some reason buttons 4 & 5 didn't translate through my steam streaming client to the host (which is also linux). I finally hacked it out. It requires a spare keyboard key that you don't use for anything. Simple script, simple apps
xbindkeys
xdotool
xev
/home/"$USER"/.xbindkeysrc
Code:
"/home/jason/.steam/numlockfix"
b:8
B:8 translates to button 4 on my logitech mouse. Use xev to confirm button identity.
numlockfix script
Code:
#!/bin/sh
pgrep steam && xdotool key F12
Couldn't find any other way to do this with XFCE. But it does work. I need to narrow the pgrep to the exact thing I'm running as I use it to run wine games from remote. But seems to work just fine.
Is a shame this isn't working properly linux > linux. The buttons already work linux > windows host. Who knows. Solved it though.