[css-fonts-5] Define behavior for <meta text-scale> from #12380

[davidsgrogan]

Initial definition of <meta name="text-scale" content="..."> resolved on in #12380

[davidsgrogan]

Hi @JoshTumath , this is my fork of Keith's initial PR. I left the definition of env(preferred-text-scale) in css-env-1 and just referred to it from here. Even though this PR is not fully complete (I didn't mention media queries, for example), I'm hoping to get it in as a kind of MVP spec. Let me know if you think something major is missing and definitely let me know if something is not correct.

[fantasai]

Also, in general, please follow https://rhodesmill.org/brandon/2012/one-sentence-per-line/ :)

[davidsgrogan]

Also, in general, please follow https://rhodesmill.org/brandon/2012/one-sentence-per-line/ :)

Thanks for pointing that out.

[JoshTumath]

Hi @JoshTumath , this is my fork of Keith's initial PR. I left the definition of env(preferred-text-scale) in css-env-1 and just referred to it from here. Even though this PR is not fully complete (I didn't mention media queries, for example), I'm hoping to get it in as a kind of MVP spec. Let me know if you think something major is missing and definitely let me know if something is not correct.

This looks great! As far as I can tell, it covers everything in the Explainer.

Should the font-size section of the spec also redefine the absolute size keywords in relation to the meta tag/env var?

Once this is merged, we'll need to add the meta extension to this WHATWG wiki page: https://wiki.whatwg.org/wiki/MetaExtensions

[davidsgrogan]

@fantasai I'd love to get another round of feedback on this, or a stamp of approval if it's sufficient as is!