Review for Expression Search / GMailUI by developernotes
Rated 4 out of 5 stars
You can modify the install.rdf file contained within the .xpi and change the em:maxVersion value from 2 to 3. Not everything appears to still work, but at least you get j/k navigation back within Thunderbird 3.
This review is for a previous version of the add-on (0.6).To create your own collections, you must have a Mozilla Add-ons account.