I had the same crash again this evening, while browsing Facebook with Firefox browser. Here is my Xorg.log.old (after reboot)
** Attachment added: "Xorg.0.log.old" https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1871873/+attachment/5350890/+files/Xorg.0.log.old -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1871873 Title: Xorg becomes unresponsive occasionally when system is under heavy load. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1871873/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs