[JS] Ship Intl.DurationFormat proposal

[Rumyra]

Acceptance criteria

• The listed features are documented sufficiently on MDN
• BCD is updated
• Interactive example and data repos are updated if appropriate
• The content has been reviewed as needed

For folks helping with Firefox related documentation

• Set bugs to dev-doc-complete
• Add entry to Firefox release notes for enabled/preview features
• Add/remove entry to Firefox experimental features page for preference/released features

Related Gecko bugs

https://bugzilla.mozilla.org/show_bug.cgi?id=1933303

Other

• Check content open issues to see if any pertain to the subject matter. If there are any that can be closed because of the work, do so. If there are any that can be fixed relatively quickly because of the knowledge from completing this issue and you have time, feel free to go ahead and fix them.

[hamishwillee]

@Josh-Cena Do you think Intl.DurationFormat needs interactive examples? Many other APIs do, but not this one.

Status

• BCD Updates for Firefox 136 beta browser-compat-data#25853
• Docs - seem OK. Note decided not to add interactive examples in this round.
• Release note/Experimental features Ff136 Intl.DurationFormat release note #38075
• dev-doc-complete

[Josh-Cena]

I'm not particularly enthusiastic to add them, but I'd be glad to review any additions. We would at least wait until #38023.

[hamishwillee]

I'm not particularly enthusiastic to add them, but I'd be glad to review any additions. We would at least wait until #38023.

Fair enough. I "like" them only because JavaScript section chooses not to have live examples, which I really like. They are the "picture that tells 1000 words".

[Josh-Cena]

For me, live examples take extremely long to load for some reason. And JS examples themselves need minimal setup to work—you can literally just copy them into the browser console, unlike web API examples which you need HTML+CSS too. What you said is totally reasonable though and I like the idea that every JS page should have an interactive example.

[hamishwillee]

every JS page should have an interactive example.

Yeah. FWIW I prefer live examples to interactive examples because the code is with the page and part of the review and test cycle for that page.
Interactive examples benefit from having the console infrastructure included, but are a bit of a hassle to set up.

[Josh-Cena]

#38023 will move interactive examples into content, making them at least as convenient to author as live examples 🔥