https://bugs.freedesktop.org/show_bug.cgi?id=108979
--- Comment #5 from Timothy Arceri t_arceri@yahoo.com.au --- Ideally you would try building Mesa from git and do a git bisect to find the commit that broke things. Or if you can do that you could try getting an apitrace [1] of the issue so that someone else can bisect it.
[1] https://github.com/apitrace/apitrace/wiki/Steam