I often have many tabs up at a time, and will sometimes want one from position 8 to be moved to position 2. Normally, I would just click and drag 8 over to the 2 spot, but now I click and try to drag and nothing happens. I ca click and drag on my desktop, and the scrollbar, and everything else, but when I click on an active tab in Firefox now it just does nothing.

I wish a screenshot would help, but it can really only be seen as it happens (or doesn't happen, as the case may be).