Thanks Olivier. I was able to reproduce the issue with that firefox (63.0b14), and the upstream bug can be found at https://bugzilla.mozilla.org/show_bug.cgi?id=1499825 .
** Bug watch added: Mozilla Bugzilla #1499825 https://bugzilla.mozilla.org/show_bug.cgi?id=1499825 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1796979 Title: Intermittently can't connect to the server To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1796979/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs