Developer reply by Robert Siebeck
Rated 3 out of 5 stars
It's good but it only works with one email at the time. If we select several emails, it does not move them. It does nothing when several emails are selected.
This review is for a previous version of the add-on (2).Multiple messages can now be moved starting with version 4.
To create your own collections, you must have a Mozilla Add-ons account.