Review for Send Filter by Roadrunner
Rated 5 out of 5 stars
I would reckon that one could start to regard this addon as superfluous if you use the latest versions of Thunderbird (I use v45.0). You can activate moving of mails to a particular folder with 'After Sending' in the filters. Problem is, as I have encountered, it does not always do that. Instead some messages for some addressees end up in the 'Sent' folder. This addon actually fixes them!
To create your own collections, you must have a Mozilla Add-ons account.