New issue by sburris0 on void-packages repository

https://github.com/void-linux/void-packages/issues/22477

Description:
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### System

* xuname:  
Void 5.4.43_1 x86_64 AuthenticAMD uptodate rrmFF
* package:  
firefox
xorg-fonts

### Expected behavior
Fonts in Firefox should look nice

### Actual behavior
Pages such as https://github.com/void-linux/void-packages have jagged, ugly fonts everywhere.

### Steps to reproduce the behavior
1. Install a font package
2. Open Firefox to a page such as this

### Fix
I found this fix on r/voidlinux: https://www.reddit.com/r/voidlinux/comments/fa9wyk/solution_for_non_antialiased_fonts_in_firefox_and/

The solution is to symlink fontconfig config files then update the font cache.

```
ln -s /usr/share/fontconfig/conf.avail/70-no-bitmaps.conf /etc/fonts/conf.d/70-no-bitmaps.conf
fc-cache -fv
```

The issue explained on arch wiki, in the context of PDFs: https://wiki.archlinux.org/index.php/Font_configuration#Helvetica_font_problem_in_generated_PDFs

I think that if this can't be fixed with a `post_install()` in a package, then a message following installation or a mention in the handbook would be helpful.