I have a new computer with Ubuntu 16.04 LTS installed.
When launching firefox, I have to wait several minutes for the start page to appear. I just have this:
Once I'm finally on the start page, the navigation is perfectly normal. I tried to reinstall firefox and to run it on safemode, but none of these solved my problem. I first thought it was a connection problem, but it's not, since Chromium works just fine.
Best Answer
I admit this to be an oddball answer but here I find I need to reboot my DSL Router when connectivity to the outside world slows down: Firefox, ansiweather (Terminal-based weather utility), etc. To me everything in the Router's web pages look fine -- 40-50% memory usage, etc. Boot the Router and I'm back to full speed for another month or so. HTH.