Форум поддержки Thunderbird

Could not find anything in add-ons, settings, or about:config. There is a topic on this site https://support.mozilla.org/en-US/questions/1086884 but I am not able to follow it because there is no add-on or plugin to enable or I cannot find it.

Has anyone found a way to have a separate "reply signature?"

The use-case is that I may send an initial email with a 'complete' signature (first name, lastname, email, phone, etc.). But when the other party replies it would be nice to then reply to that with just my first name. Or at worst, auto-insert the full signature.

I've setup my full signature and auto-populates when I create a new message. But not on the reply.

Any suggestions?