Where can I tell Thunderbird always to send emails as plain-text, and never as HTML-formatted messages? I hate HTML-based email, and always do everything possible to send my emails as plain text.
Thunderbird is always pestering me with questions like "This recipient cannot receive HTML..." or "In order to sign this email, it needs to be converted to plain text..."
Is there a way I can simply say to Thunderbird "Look, old chap, it's all plain text, so don't bother me any more, ever, again"?
Uncheck Tools -> Account Settings -> Composition & Addressing -> Compose messages in HTML format