I found this bug after reading this post:
https://forums.mirc.com/showflat.php?Cat=...amp;amp;fpart=1
The post made me wonder if you could use /font with uninstalled .fon files that exist in the mirc folder. I downloaded a .fon and put it in my mircdir, then tried this:

//font $active " $+ $mircdir $+ newfont.fon"

Nothing happened... Then I typed /font to open the font dialog.

*CRASH*

When it crashed, it left my font with the path in mirc.ini and every time I type /font in that channel it crashes again.

I removed the line from my ini and no more crash on /font

mIRC 6.14, WinXP Pro SP1, A7N8X-Deluxe + AMD XP2500+ Barton