My filed bug can be found at https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1891790
(I’m still trying to run apport-collect, since I was unable to file on an impacted box using ubuntu-bug)
Also note, I’ve had this issue on two of my boxes
ibm thinkpad t42p (pentium m, 2gb ram, amd/ati mobility firegl t2; rv350/m10 gl)
ibm thinkpad r50p (pentium m, 1gb ram, amd/ati mobility firegl t2; rv350/m10 gl)
and I’ve noted users also report the same issue on a t41 and of course your x31