1) Download greasemonkey (direct link here). Install your add-on as usual. 2) Download the TextBoxMate script after you've installed greasemonkey and restarted Firefox if necessary (click here for a direct link). 3) You should get a pop-up saying it's been directly installed. 4) You're done! The hardest part is USING IT. You can't really right click and get an option to check them all. So. You have to right click on a box and drag your mouse up/down. Like so: