I've been having some odd problems with Firefox recently: I'd given up, temporarily, on version 1.5 and gone back to 1.0.7 and then, earlier today, for some unknown reason, it crashed and disappeared from the screen. I re-launched it, but it wouldn't load pages and not all of the menu buttons functioned. So... I downloaded version 1.5 to give it another try, but I kept getting the same message about being unable to load extensions because of some java problem; and the information isn't specific enough to let me know what kind of problem.
So I downloaded the Maxthon browser, which runs on the IE engine: it's got tabbed browsing and does pretty well everything that Firefox does and I think it is actually a little bit faster. However, last thing I've done is to download Firefox 1.0.7 again and install it - it now runs OK, but won't launch reply windows for my webmail system. So perhaps I'll have to become an advocate for Maxthon. Is it my imagination, or does Firefox generate a crop of problems with each new release?