Comment 14 for bug 1749779

Because I did not want to leak any personal data in the crash files, I reinstalled an Ubuntu 17.10 on another hard drive to have a fresh generic installation and did the tests there before rebooting on my regular installation.

There are two crash files, one for gnome-shell, the other one for XWayland. I put them in a zip file and, as it seemed big to me, I uploaded the file on my web server:

http://mess.psydk.org/c18b_crash_firefox.zip

Other observations:
 - I tested the problem with a X11 session, and I can reproduce it.
 - I tested the problem on Ubuntu 16.04 and I could not reproduce it.
 - I've been looking at Firefox source code, it calls gtk_window_fullscreen(). I wrote a program to repeatedly call that function but I cannot make it freeze. There is some specific X11 code in Firefox though that I did not integrate in my test program.

Otherwise, are you able to reproduce the problem on your side? It seems quite easy to get. I will test other Ubuntu 17.10 installations tomorrow to get more statistics.