See the easiest way to create and set up an automatic email signature in Thunderbird. Written by Kamil Glaser Updated: July 13, 2026 Posted: August 19, 2015 Mozilla Thunderbird continues to be one of the most popular free email apps. In this article, I’ll show you how to add an email signature in Thunderbird. But first, … Continue reading How to add an HTML email signature in Mozilla Thunderbird