Looking at get support in formatOptions for graphical measurements like "pixels", "points", and "picas", I've recently been reviewing the growing number of "please add these unit" issues in this repo:

• Add Units mass-metric-ton, volume-cubic-* #605
• Add graphics units to NumberFormat #503
• Add 100-kilometer unit to NumberFormat #470

And found that starting from tc39/proposal-unified-intl-numberformat#39 the team has been looking for ways to contain the shipped units/translations so as to keep browser builds down.

In support of that goal, I wonder if there would be appetite for a user space partnership with a proposal like #434 wherein additional units could be added to the browser API from the outside as opposed to or as well as from within the browser? Much like we see in the @formatjs/intl-numberformat polyfill for this API, were there to be a Intl.NumberFormat.__addLocaleData equivalent method built into the NumberFormat API a user could load new translations to be leveraged by the browser directly within the API without having to have innumerable values supported by default.