Rated 5 out of 5 stars

Such an amazingly simple to use extension! I love it! Can you get it to work with version 78 of Thunderbird? It's so useful to me.

This review is for a previous version of the add-on (2.1.1.1). 

There is a new version supporting Thunderbird 78 in review by Mozilla.
It is now at GitHub https://github.com/nattoheaven/macrotemplate.