Review for MinimizeToTray by anilklella
Rated 5 out of 5 stars
As previous user mentioned, if you are not comfortable or do not know how to change install.rdf file, please see the following link -- at the bottom you will find the modified xpi file to install directly.
http://www.geekishblog.com/2008/08/modify-incompatible-firefox-extensions-to-make-them-work-with-firefox-3/
To create your own collections, you must have a Mozilla Add-ons account.