The new Address book tab is incredibly annoying. When I open the Address book and look up a name aand then go back to the Inbox it "resets" the email that I had been viewing so I have to re-scroll down the entire email to find out where I was reading! I want to have the option of still opening up the Address book as a completely separate window, just as before -- but NOT by opening up an entire "duplicate" of the Inbox and (Unified) Folders. I know that Mozilla added the option (right click) "Move to New Window" but it's incredibly slow and annoying to have to do that EVERY TIME that I open the Address book tab. It should be made as a PERMANENT option that USERS can decide how the Address book behaves, either as a "Tab" in the main window (the new config) or just as the Address book functioned before (as a separate window), which I personally PREFERRED **much more** than the current configuration -- mostly because I could Alt-Tab and switch Extremely quickly (in a matter of milliseconds) between the Inbox and the Address book (using my keyboard) WITHOUT the software "resetting" the email that I am currently viewing.
