Rated 5 out of 5 stars

le Kal.El ar Ean. 18, 2010 · buan-nasc

You can make it to work with TB3. You just need to unzip it (XPI is ZIP file), edit file install.rdf, find 3.0b2 and modify it with 3.1 , save file, compress all files to ZIP again, rename extension from ZIP to XPI and it's done - you can install and run it with TB3