Better Firefox font rendering with ClearType on Windows

I use RunCloud for managing my VPSs. I noticed that the dashboard icons look bad on Firefox, while on Blink-based browsers such as Chrome and Edge, they look smooth. Check out this side-by-side:

Firefox
Chrome/Edge

I much prefer the way Firefox renders fonts, especially on thinner fonts which seem to be all the rage these days since iOS 7. A lot of them are hard to read on Chrome/Edge and Firefox renders them a lot clearer on Windows 10.

This icon font rendering is not good though, so I did some investigating and found this line in about:config:

gfx.font_rendering.cleartype_params.rendering_mode

These are the options I found associated with it:

  • -1 or 0 = use default for font & size
  • 1 = aliased
  • 2 = GDI Classic
  • 3 = GDI Natural Widths
  • 4 = Natural
  • 5 = Natural Symmetric

I chose option 5 (default -1) and rendering is a lot better now:

Before
After

It could still improve a bit, but at least it’s not as jaggy as before.

Leave a Comment