[RndTbl] firefox font weirdness?

[Trevor Cordes]

Has anyone noticed that newer/est(?) Firefox 123 (123.0.2) suddenly made
the fonts all weird in some cases?

Like the default fonts were changed, and/or entire relaed css definitions
like line height?

I have a simple web page with no css set and no font settings and it
suddenly looks very different, with the font just "wrong" and line height
set very strangely.  If I click webdev inspector it doesn't tell me what
font it's using, so it must be the firefox default.  Settings says that's
bitstream vera serif / vera sans.  I really have no way to see what the
default was before?

Worse, a forum site I frequent suddenly has the textarea box go mental on
the font and line height.  But only in firefox, and never before v123.
The inspector shows

font-family: DejaVu Sans Mono,Monaco,Consolas,monospace

font: 83.33%/150% Segoe UI,Helvetica Neue,Nimubs Sans L,Arial,Liberation
Sans,sans-serif

(I have no clue what the % prefixes are for in the font setting.)
Inspector says all the heights and related font- stuff is normal.

The font looks like a decent sans, but in no way is it monospaced as the
family indicates!  If I type in numbers, they come out lighter gray (vs
the normal black text), and line height is normal.  But if I type a single
letter on a line, all of a sudden that line gets about half-line-height
padding above and below itself!  I can send a screenshot if desired.

In Chromium all of this stuff works and looks normal (as firefox used to).
And the mono font really is mono on that forum textarea.

Is anyone else have font weirdness with firefox 123?  Anything I can try
as a fix?  Maybe I'm missing some fonts?  The only font-y thing I've done
in the last year is try to get that new Monaspace stuff installed and
working in gnome-terminal, but even that hasn't been toyed with in over a
month.

If someone has firefox <122 installed still, what are the default fonts in
the settings?

Thanks!