Hi webkit-dev,

I'd like to request an official position on @font-face descriptors `ascent-override`, `descent-override` and `line-gap-override` for overriding the default font metrics.

Explainer: https://gist.github.com/xiaochengh/da1fa52648d6184fd8022d7134c168c1
Spec: https://drafts.csswg.org/css-fonts-4/#font-metrics-override-desc
Chromestatus: https://www.chromestatus.com/feature/5651198621253632

Other information:

These descriptors are newly added into CSS Fonts Level [1], following a recent resolution [2].
Chromium has already implemented them in M86 behind a flag [3].

[1] https://github.com/w3c/csswg-drafts/pull/5521
[2] https://github.com/w3c/csswg-drafts/issues/4792#issuecomment-693528301
[3] https://chromium-review.googlesource.com/q/hashtag:%22font-metrics-override%22

Thanks,
Xiaocheng