Rated 3 out of 5 stars

I have downloaded the version 3.8.1, get the error message that program is corrupted.
Use Thunderbird 64.0.2 (64bit)
Greeting André

This review is for a previous version of the add-on (1.2). 

Where in the lords name did you get version 3.8.1? Official version here at ATN is 1.2 and it is compatible with TB 60.