Why is the elegant, community-built application suddenly behaving badly? In our poll, readers rated Firefox’s mysterious habit of gobbling up every remaining scrap of a computer’s memory their No. 1 gripe about the browser. Complaints of slow performance and instability ranked highly as well.
I have found myself becoming increasingly annoyed with Firefox performance, even though I run a rather speedy system. Personally though, I run into more bugs than I do performance issues, such as when a website will break out of the actual browser, causing it to crash.
I too, would like to go back to the old days of a slimline browser. Of course, extensions are not helping anyone either.
Source: Wired.com