Puntuado con 5 de 5 estrellas

I made the required changes to run the add-on in Thunderbird 68. To provide this update, the initial developer is asked to accept this contribution.

Esta valoración es de una versión anterior del complemento (1.4). 

I've been extremely busy lately to have a look at this.
If you have made changes to make it compatible with the new version of TB and have a way to share it with me, I'll be happy to submit it as the new version.