Rated 5 out of 5 stars

by spidey9 on ژوئن 9, 2015 ·

It is annoying that this extension is even needed - it should not require an extension to simply change a default setting. However, there is no provision in Thunderbird for setting the default Outgoing Message Format to anything other than "Auto-Detect.

This extension provides that functionality, and does it perfectly. My heartfelt thanks to the developer(s).