I can't get Thunderbird 13.0.1 to use proper font sizes for message text.
I have configured all font settings to use Ubuntu Mono 16, and set minimum font size to 16. Nevertheless, I get two different font sizes for message bodies depending on the encoding specified in the Content-Type header, both of them wrong.
When the encoding is omitted, or when it is set to iso-8859-1 or us-ascii the message is displayed using a font that seems to be of size 12 or 13. This font size is also used when composing new messages. When increasing the configured font size, the displayed text increases size and seems to stay about 3 or 4 units below the one I set.
When the encoding is set to utf-8, the message is displayed using a very tiny font, size 8 or 9. This is close to unreadable. The font size used for such messages are constant, and does not change when I modify the configuration for fonts or minimum font size.
I had similar problems with earlier versions of Thunderbird, but it has gotten a lot worse after the last update, with the font size for utf-8 messages refusing to increase above the unreadable.
Is there any way to circumvent this annoying problem?
