Now that I have time on my hands, I'm curious about the problem. I set up an Arch Linux VM, with Plasma 5 (The whole shabang) and installed steam. When I try to start it (from a terminal) I get this error:
libGL error: unable to load driver: swrast_dri.so libGL error: failed to load driver: swrastConsidering that this is probably a video deiver error, I'm not at all surprised I'm getting it here (I doubt VirtualBox guest additions' drivers are supported), but I had the same issue running natively with xf86-video-vesa and xf86-video-intel, and it had previously worked.
I already tried some possible solutions back then, which included puring Steam files $HOME and re-installing them, but this didn't change anything. Anyone got any ideas?
PS. I probably will switch back to Arch before my next year at college, whether I can get Steam to work or not... I miss the cutting edge side of things.
Edited by Dr. J, 28 May 2016 - 10:52 AM.