Isn't the article saying they added a new css element, but it's not restricted to apple apps only really, just not in documentation yet? for example, this article is preview documentation, of a sort?

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thefreeman a day ago | parent [-]

No, it says it is restricted. You need to set a private attribute on the webview to enable it. And if you interact with private APIs your app will be rejected in review.

	▲	jjtheblunt a day ago \| parent [-]
		I understand, though conjecture (worked at apple for years) this looks like an imminent "feature" that will become documented.