Even worse, it started taking much longer than average loading up normal web pages. It would spend many seconds “looking up domains” (which might suggest a DNS issue). What’s odd is that it would do that after a few pages have been opened (i.e, it won’t happen when you first run firefox). However, i didn’t change my network configuration at all.
Anyway, this is all to say that something is wrong with the latest version of Firefox (version 18.104.22.168) and apparently other people have been experiencing this too. If you have been facing these problems (specially pages taking infinitely long to finish loading), i suggest rolling back to a previous version. I went back to 22.214.171.124 and that seemed to work fine. But don’t worry, i think the Mozilla community will release a fix soon.