I have my font settings setup as so:
My devtools use the default font rather than the monospace one setup in Advanced settings:
I’ve tried fixing this through userChrome.css but I had no luck. The only “solution” so far is setting the default font to a monospace one, but that affects webpages as well, which is less than ideal.
I am on Arch Linux 5.7.12, using Firefox dev edition 80.0b4 (64-bit), but the issue also appears on my install of regular Firefox 79.0 (64-bit).
Is anyone else experiencing this?