Still working! Rated 5 out of 5 stars
Works fine, even with FF5. You just need to Download the addon as file open .xpi as archive and install.rdf as txt Search for "em:maxVersion="6.*" /&gt;" and change it like this :) then it will even work in FF6 ;) maybe....
Edit: Still works in Firefox 12!
Love it! Couldn't live without that addon!
The only thing that i miss is that you only have 3 custom resolutions/positions.