This commit is what's causing the hang: https://hg.mozilla.org/releases /mozilla-beta/rev/5f0dcca70da9.
I did a test build without --enable-stdcxx-compat, which is what triggers this code to be built, and isn't required any longer, because since https://bazaar.launchpad.net/~mozillateam/firefox/firefox.xenial/revision/1391 we're statically linking against the libstdc++ in gcc-mozilla, and the hang at startup is gone. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1885159 Title: Firefox 78.0 RC hangs at startup on Ubuntu 16.04 Status in firefox package in Ubuntu: Confirmed Bug description: After latest FF beta update - Firefox doesn't start (also there is no crash). In system monitor Firefox process is visible, but still app doesn't appear.Starting in safe mode doesn't help. Previous version: 77.0.1+build1-0ubuntu0.16.04.1 Updated version: 78.0+build1-0ubuntu0.16.04.2 Ubuntu version: Ubuntu 16.04.6 LTS Apport bug report attached. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1885159/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
