Review for Get before Send by jwheck
Rated 5 out of 5 stars
Works as advertised. Be sure to add the Get->Send button to the toolbar on the composition window (not the main window) to get the maximum benefit of this add-on.
This add-on helps if you are getting the "sorry, that domain isn’t allowed to be relayed thru this MTA (#5.7.1). Please check the message recipients and try again." error.
To create your own collections, you must have a Mozilla Add-ons account.