Review for Gmail Manager by James Ayton
Rated 5 out of 5 stars
I got this add-on to work perfectly with the new Firefox 3.6 using the "Add-on Compatibility Reporter" add-on located at: https://addons.mozilla.org/en-US/firefox/addon/15003
After you install the compatibility add-on, you have to restart Firefox twice.
To create your own collections, you must have a Mozilla Add-ons account.