User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0.1) Gecko/20100101 Firefox/4.0.1 Build Identifier: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0.1) Gecko/20100101 Firefox/4.0.1 If I fire up Firefox and open a website I've got a lot of history with (say, Metafilter) it is its normal peppy self. If, in comparison, I open "Show All History" first and search for Metafilter, and leave that open while I go and load up Metafilter, something (that I suspect is the search being re-run in full every time I hit a new metafilter page) stomps on my performance, making stuff that used to take a fraction of a second take as long as half a minute in some cases. This works with bugzilla, too. Reproducible: Always Steps to Reproduce: 1. As described above. Search for a frequently visited site in History, then open that site. 2. Pinwheel! Actual Results: Slooooooooow. Expected Results: Fast! Thanks!