I've been loyal to Firefox ever since it came but recently it disappointed me. First, it happened when I had to switch to a new laptop in my workplace and I relied on Firefox sync to keep all those bookmarks etc. but when I switched, all were gone, absolutely nothing. I thought, ok there was a bug maybe.
Now every time there is new version of Firefox it tells me that I have to create a new profile because the older version corrupts the existing profile and so it's totally becoming useless.