Chromium new font rendering backend

[maximilionus]

No more FreeType

Starting from Chromium 133 release, it no longer uses FreeType to render fonts and, as expected, no longer respects any FreeType configurations. Instead, the self-written Rust project called Skrifa is used now for font rendering.

Google developers justify this change as a more memory-safe approach to the font rendering in their blog post.

What's broken now?

The full scale of broken stuff is yet to be determined, but multiple reports, including #14 from this repo, state that one of the main goals of this project, stem-darkening (in nutshell, small size fonts emboldening) is basically dead for now, as Skrifa completely ignores those parameters.

So what now?

At the quick look I made on Skrifa repo, there are no visible ways to set the settings the way FreeType allowed us to do, and considering the project goal "safety first and foremost" - I have a hard time imagining that something like that will be possible ever. But we'll see.

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Update 1: Temporary solution below.

Update 2: Chromium completely dropped the FreeType support. More detailed report here.

[maximilionus]

Small comparison image for the reference. Left to the right: Brave 1.78 > Chromium 136.0 > Firefox 136. Stem-darkening does not work in both Chromium browsers.

[maximilionus]

Skrifa rendering library completely lacks any stem-darkening functionality (googlefonts/fontations#1407), as the ability to configure it (googlefonts/fontations#1493).

[maximilionus]

As a temporary solution, Chromium allows disabling the Fontations backend through flags:

1. Open this link in Chromium: chrome://flags/#enable-fontations-backend
2. Set the flag to Disabled.
3. Restart the browser by closing the window, not by pressing the restart button.

This also applies to any Chromium based browsers and software.

Fontations is a new font rendering system and Skrifa is one of the components in it.

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• Before:

• After:

[alexjp]

For completion, the command line flag is:
--disable-features=FontationsFontBackend

[maximilionus]

@alexjp that's very handy, thanks for sharing. Now I wonder if there's any replacement for the now deprecated CHROMIUM_USER_FLAGS env. variable feature, to disable the Fontations automatically.

[alexjp]

@alexjp that's very handy, thanks for sharing. Now I wonder if there's any replacement for the now deprecated CHROMIUM_USER_FLAGS env. variable feature, to disable the Fontations automatically.

Not that I know of. The way I set it up is to have an environment variable with all the switches and then running the application in a script like:

#!/usr/bin/dash
. /tmp/.alex/env-chrome.sh # where all the switches are for this session/desktop environment
exec /usr/bin/brave "$@" $CHROMEPARAMS

[maximilionus]

Got some bad news here. Received a few user reports that Fontations switch flag is now gone from Chromium, so I decided to make a little investigation.

Turns out that the the Fontations switch flag is now completely removed from Chromium¹, and one of the Fontations contributors states that they "...no longer intend to carry the FreeType support."².

This change is rolled out in Chromium 139.0.7258 and now there are no ways left to switch the FreeType rendering back, except for manual patching, but that's an overkill solution as for me and is completely not possible for proprietary Chromium-based software (like Discord and others).

There's nothing more I can do here other than suggest switching your browser to Firefox, at least until the Fontations stack matures enough to support the required functionality (mostly stem-darkening).

Footnotes

1. https://chromiumdash.appspot.com/commit/2fc1ae192a45eb6f1716e232dd1626317f8d299e ↩

2. https://github.com/googlefonts/fontations/pull/1496#issuecomment-3004330901 ↩