I have just upgraded Thunderbird to 52.1.0 (32 bit) from a much smaller number. I used to be able to compose all messages and replies in my default font of Calibri. Now I'm getting Times sometimes. I read an explanation which says:
When you reply to a message, it is normal to use the same encoding as the incoming message. So if you haven't actively set other encodings, you'll get the defaults, which may well be tiny Times Roman.
The source doesn't say what to do about the problem.
What can I do with my settings to consistently send all my email in the same font (preferably Calibri)?
Best Answer
I don't know if this is a bug or what, but what made things stick finally, for all email message responses, was to UN-check "Use Paragraph format instead of Body Text by default":