how to keep a set font as default

[fbu924]

Hi, I think this is a build "something" (bug?). On one trial using stable portable t-bird 24, the problem did not occur.
-Earlybird 32.0a2 daily updated,w8.1.1. Even though in options I set the font to Arial, inevitably when I open a new "compose" window, it shows "mixed" fonts, not Arial. And the font sizes are noticably different, starting slightly larger on the first line, then going to smaller size on subsequent lines.
-Do I need to set something in .css to fix this in the build? Are there example scripts out there? I'm not a formal coder but have changed the occasional .css a few times. Thank you.

[tanstaafl]

The reason it might not occur with portable Thunderbird is because it (normally) uses a different profile.

Did you uncheck tools -> options -> display -> formatting -> advanced -> "allow messages to use other fonts"? I'm also using Earlybird 32.0a2 (2014-07-07) and don't seem to have that problem. You might also need to set the "minimum font size" in the advanced font settings.

[fbu924]

Thank you. I changed as you advised. On 3 trials, restarting earlybird nightly (same version, same day, not reinstalling, etc.): the "write"window shows Arial (greyed out), as the default, which is what I put in & what I want. However, when I begin typing in the message body, the font showing the font earlybird is using ( in the box to R of "body text" button at top of message field), changes with the first stroke, to "mixed". So, it looks like the font is, yay, staying the same size consistently, but is still consistently refusing to stay "Arial."
I also searched on "mixed" & "arial" in config ed. "Mixed"only brought up under pref name, three lines beginning w/ "security" ... which I think irrelevent & didn't change. There were lots of "Arial" instances found, most of which were for unused languages, so I didn't do anything there either. So no changes made in config ed.
-I did choose the portable as a test to minimize changes to profiles. I would just like this nightly in this issue to keep its fonts. I can work with "mixed", though, as long as the font doesn't shrink as it had. & I do realize if I want stable, it's there & it works w/o dealing w/this issue at all. So thanks for the good pointers.
-Thank you.