If you have a lot of passwords this plugin is a noticeable performance hit in Firefox. It seems nearly every page freezes for a second during load while this plugin does its thing. I also don't understand why reviewers rave about its interface -- it seems to me the nagging popup panel puts itself in the worst position on-screen, often blocking the view of critical interface elements on the page. I wish the popup dialog would only display if I pressed the little lock icon. I have not tried a lot of different password managers, but this plugin needs some improvement in my opinion.