On my Macbook, Firefox is slow. Really slow. It takes about 30 minutes to start up - when I wake up, I start it, and once I am done breakfast, it's usually done. And, it takes a super-duper long time to shut down - I haven't shut it down one, I just force close it now because it takes so long. It shouldn't be - the rest of the applications on this machine are really fast, and Safari starts instantly - but I love Firefox and don't want to leave it. How can I fix this problem?
Edit: I disabled all extensions which makes it start up almost instantly now, but it still will not shut down.