> AFAICT, this is a web standard and expected to get buy in from Safari and Firefox before shipping to users.

If it hasn’t already got buy in then it isn’t a web standard, it’s just a Google proposal. Something isn’t automatically a web standard just because Google thinks it’s a good idea.

Here are Mozilla and WebKit positions on this:

> This proposal attempts to solve multiple problems with a single solution. We (Mozilla) recognize the motivation for solving some of the problems, but believe that this is not the right solution to each problem, or in some case a step in the wrong direction.

— https://github.com/mozilla/standards-positions/issues/1076

— https://github.com/WebKit/standards-positions/issues/630

As far as I can see, nobody outside of Google has committed to implementing this.

From the discussion linked in the Webkit repo:

--- start quote ---

Philip: First, google slides is written in svg, so that won't change with this. But google docs is using canvas, so they might be a candidate. … they might want to integrate this peicemeal, this API allows them to start to adopt the feature slowly,

--- end quote ---

This reads to me like "Google Docs decided to go with canvas sometime ago [1], found it to be too hard, so pushed Chrome to have a way to support HTML in Canvas. The rest is just post-hoc justifications"

[1] https://workspaceupdates.googleblog.com/2021/05/Google-Docs-...