1761043 - Implement hidden=until-found attribute and beforematch event

Status: UNCONFIRMED

(Core :: DOM: Core & HTML, enhancement)

Description

[Joey Arhar]

User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.46 Safari/537.36

Steps to reproduce:

This feature was added to the HTML spec here: https://github.com/whatwg/html/pull/7475
Here is an explainer: https://github.com/WICG/display-locking/blob/main/explainers/hidden-content-explainer.md

The "until-found" value for the hidden attribute should make the element content-visibility:hidden instead of display:none. When the browser searches for text via find-in-page or ScrollToTextFragment, it should also search for text in hidden=until-found elements. If find-in-page or ScrollToTextFragment want to scroll to a match inside a hidden=until-found element, it should remove the hidden attribute from the element and fire the "beforematch" event on it in order to reveal the match.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::DOM: Core & HTML' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Jeff Muizelaar [:jrmuizel]]

Wikipedia uses this attribute now which means find in page works much better in Chrome on Android than in Firefox