Comment 118 for bug 691380

I can promise you that you will be happy with the next release of the Unified Search addon. I'm kind of a beta tester for it and the last beta I got is great. It allows you to hide all the new stuff and just have a filter box in the button bar with either a dropdown or a horizontal bar (like shown above) that can be used like in TB2. It has many more features for using the new TB stuff also, but if you like you can just revert to the TB2 behaviour. It has additional useful options like keeping or deleting (like TB2) filter options on restart etc. which TB3 does not have.
From the current beta state I guess an official release won't take too long now, so stay tuned :-)