Rated 5 out of 5 stars
But can it works with RSS-accounts?This review is for a previous version of the add-on (0.9.1).
Archiving of RSS accounts is not possible in Thunderbird. Therefore the addon can't do it.
Maybe you can create a Filter which moves the RSS messages to a folder inside a POP3 account. Then you can archive this one. Sounds a bit tricky but may work.