Very good! Rated 4 out of 5 stars

The only issue I've had with this extension is that, rarely, history items are still visible until after a browser restart. A very minor issue. I can also confirm that Stealther, in its current state, is capable of running on the new Firefox 3b1. Simply, save the XPI installer (the file you click to install) to your machine, open it in a ZIP program, edit the data "2.0.*" to read "3.0.*", and drag into Firefox.

This review is for a previous version of the add-on (0.99).