Comment 30 for bug 1772542

Chris Guiver, you may need to use:
sudo ubuntu-bug /var/crash/FILENAME.crash

when filing crash reports in order for the upload/uploaded files to be generated, and, in turn, to get the errors reported successfully.

Given the reproducibility of the crash, and how you are using the latest Ubuntu release, I'll mark this Triaged for now, and an xorg developer may further review.