New comment by PurpleVsGreen on void-packages repository

https://github.com/void-linux/void-packages/issues/31294#issuecomment-858921154

Comment:
I put this in `userContent.css`:

```css
@font-face {
	font-family: Courier;
	src: local("DejaVu Sans Mono");
}

@font-face {
	font-family: Helvetica;
	src: local("DejaVu Sans");
}

@font-face {
	font-family: Times;
	src: local("DejaVu Serif");
}
```

It goes in a (new) directory called `chrome` (lol) inside the FF profile directory. It can be opened with a button in `about:support`. In `about:config`, `toolkit.legacyUserProfileCustomizations.stylesheets` has to be `true`.