Assegnate 5 su 5 stelle

But can it works with RSS-accounts?

Questa recensione riguarda una versione precedente (0.9.1) del componente aggiuntivo. 

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.