This is the worst upgrade of a product that I generally like. My trackpad functionality is nil, which is ridiculous. Also, all my tabs were lost (there was no button for 'restore tabs,' so I don't know how it went wrong). Reinstalling version 3.6, which apparently won't be supported much longer doesn't make sense, but I am really incensed. Was there no beta testing on Macs? How can you take away the functionality of an important piece of hardware? I see that there are patch fixes that other members have come up with to try to get that functionality back in some form, but it is YOUR job to fix this, or rather, have prevented it altogether. My missing tabs are toast, I know that, and I'll never figure out what I've lost, but I should be able to use my computer as it was designed, don't you think? And I'm not even getting into the changes in the toolbar, etc, which I don't see as a positive at all. I am so sorry I upgraded to this terrible version.