I'll try commenting out stuff from the profile today and post the results.

When using -noprofile, FF does not freeze. usr/bin/firefox will run without any additional sandboxing featuresĪTTENTION: default value of option force_s3tc_enable overridden by environment. Warning: an existing sandbox was detected. Reading profile /etc/firejail/whitelist-common.incīlacklist violations are logged to syslog Reading profile /etc/firejail/disable-devel.inc Reading profile /etc/firejail/disable-programs.inc Reading profile /etc/firejail/disable-common.inc If still no dice, the page has probably been taken down temporarily. If not, go back to the settings and check your typing. No sense keeping a non-working page listed in your links. Reading profile /etc/firejail/firefox.profile Close the browser and open the browser a moment later, to ensure the pages you'd like to open, are correct and are working links. Can you post your profile here? I can try starting Firefox with that profile to see if I experience the same using firejail version 0.9.44.8 now.still happens. This leaves either the Ubuntu version of Firefox somehow uniquely conflicting with Firejail or something in your profile. I went ahead and upgraded my Firefox to 52.0a2 and still don't see the problem you're describing.

I guess what I'm trying to get at is that my experience may not be too helpful here 😛 In addition I use a custom profile (the one that's in my repo). I just realized I'm a couple of betas behind on Firefox (51.0b5) and a couple of releases ahead on Firejail (0.9.44.8) and on Debian sid/experimental.

Side note: There have been a couple of updates to firejail recently as well, so maybe you should update (if possible) before trying all of this. (If I had the same problem, I'd help you debug.unfortunately, that isn't the case). Assuming that works fine, then comment out most of the profile and slowly uncomment lines until it freezes again. One thing you can try is to first try firejail -noprofile firefox to see if it still happens (which would indicate that one of the basic setup steps firejail does screws with firefox - unlikely).

Firefox opening multiple tabs