I have been using Firefox on Ubuntu 18.04 for several weeks. I currently have firefox 67.0 (freshly updated). Since the update, firefox cannot connect to the internet anymore. The internet is working fine. I am writing this post from the Opera browser the I installed on Ubuntu 18.04 after the problems with Firefox.
I tried to follow the suggestions of this post. Explicitly I tried the following:
- Change proxy setting, in about:preferences Network Settings. I tried the options "no proxy", "Auto-detect proxy" and "Use system proxy" (the latter was the default).
- In about:config I set the "network.dns.disableIPv6" to TRUE
- In about:config I set the "network.dns.disablePrefetch" to TRUE
The issue seems firefox-specific. Opera does not give any problem. Pinging to www.google.it works fine (so no DNS problems).
I am fine using Opera, but I would also like to understand hwo to fix the issue in Firefox!