Hey Demetrios, Thank you for raising the issue. However, I think this discussion is likely better suited for a spec venue like WHATWG ( https://github.com/whatwg/html/issues).
As far as I can tell, Blink/Chromium implements the specified behavior. It seems like this causes problems, so maybe we should revisit whether the spec should change. Thanks, Vlad On Thu, Feb 12, 2026 at 7:41 PM Demetrios Papadopoulos <[email protected]> wrote: > Reviving this older through about the hidden="until-found", since it seems > to be causing issues (newly thrown TS compiler errors with the upcoming TS > v6) due to HTMLElement's hidden property channging from a boolean to > boolean|"until-found". Plese see my comment at > https://github.com/web-platform-dx/developer-signals/issues/170#issuecomment-3894089666 > for more details. Wondering if the complications with changing the > property's type was already considered, and whether there is any workaround > beyond just trying to accomodate for the new type across a codebase. > > Thanks! > On Wednesday, March 23, 2022 at 8:25:53 AM UTC-7 Daniel Bratell wrote: > >> LGTM3 >> >> /Daniel >> On 2022-03-23 05:50, Yoav Weiss wrote: >> >> LGTM2 >> >> On Thursday, March 17, 2022 at 8:10:47 PM UTC+1 Joey Arhar wrote: >> >>> Contact emails [email protected] >>> >>> Explainer >>> https://github.com/WICG/display-locking/blob/master/explainers/hidden-content-explainer.md >>> >>> Specification https://github.com/whatwg/html/pull/7475 >>> >>> Design docs >>> https://github.com/WICG/display-locking/blob/master/explainers/hidden-content-explainer.md >>> >>> Summary >>> >>> This feature extends the existing hidden attribute with a new value, >>> "until-found", which makes the element searchable by find-in-page, scroll >>> to text fragment, and fragment navigation. When these search/navigation >>> features want to scroll to something inside a hidden=until-found element, >>> the browser removes the hidden attribute from the element and fires the >>> "beforematch" event on it so that the newly revealed content can be >>> scrolled into view. >>> >>> >>> Blink component Blink>HTML >>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EHTML> >>> >>> TAG review https://github.com/w3ctag/design-reviews/issues/511 >>> >>> TAG review status Issues addressed >>> >>> Risks >>> >>> >>> Interoperability and Compatibility >>> >>> Interoperability risks: This feature is built on content-visibility, >>> which is gradually being implemented in other browsers. The way this >>> feature extends the existing hidden attribute means that browsers which >>> don't implement this feature will still render hidden=until-found content >>> as expected, but without the new find-in-page and ScrollToTextFragment >>> auto-revealing functionality. Mozilla says this feature is worth >>> prototyping. Compatibility risks: This feature is unlikely to break >>> existing websites because they must opt-in by setting the "hidden" >>> attributes on elements to "until-found". In the unlikely event that >>> existing websites use hidden=until-found, it will just replace their >>> "display:none" with "content-visibility:hidden" which will likely render >>> the same. >>> >>> >>> Gecko: Worth prototyping ( >>> https://github.com/mozilla/standards-positions/issues/612) >>> >> >> I'll just note that this is not yet the official label, although it seems >> like it's going that way. >> >> >>> >>> WebKit: No signal ( >>> https://lists.webkit.org/pipermail/webkit-dev/2022-March/032142.html) >>> >>> Web developers: No signals >>> >>> Other signals: >>> >>> Ergonomics >>> >>> This feature can be used in tandem with scroll to text fragments. This >>> feature will not make it hard for Chrome to maintain good performance. >>> >>> >>> Activation >>> >>> This feature will benefit from having example code in the explainer repo >>> to show developers how to use it. >>> >>> >>> Security >>> >>> What the user types into the find-in-page box should not be visible to >>> websites, and the beforematch event is a new way for websites to try to >>> read this information on top of the existing scroll events. I created a >>> privacy mitigation for all of these attack surfaces for find-in-page by >>> adding a delay before find-in-page scrolls text into view when needed so >>> websites are unlikely to be able to incrementally build what the user is >>> typing into find-in-page. >>> >>> >>> WebView Application Risks >>> >>> *Does this intent deprecate or change behavior of existing APIs, such >>> that it has potentially high risk for Android WebView-based applications?* >>> No >>> >>> >>> Debuggability >>> >>> There are no DevTools features for the scrolling, URL fragment, and >>> event firing impacts that beforematch has. >>> >>> >>> Is this feature fully tested by web-platform-tests >>> <https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md> >>> ? The find-in-page portion of this feature can't be tested because >>> find-in-page can't be tested in WPT yet: >>> https://github.com/web-platform-tests/wpt/issues/29915 >>> Here are some tests which I will try to move to WPT soon: >>> https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/web_tests/wpt_internal/display-lock/beforematch/ >>> Here are WPTs for the hidden IDL changes to allow "until-found": >>> https://github.com/web-platform-tests/wpt/pull/32465 >>> >>> Flag name --enable-blink-features=BeforeMatchEvent >>> >>> Requires code in //chrome? False >>> >>> Tracking bug >>> https://bugs.chromium.org/p/chromium/issues/detail?id=1055002 >>> >>> Launch bug https://bugs.chromium.org/p/chromium/issues/detail?id=1302408 >>> >>> Estimated milestones >>> >>> 102 >>> >>> >>> Link to entry on the Chrome Platform Status >>> https://chromestatus.com/feature/5400510406328320 >>> >>> Links to previous Intent discussions Intent to prototype: >>> https://groups.google.com/a/chromium.org/forum/#!searchin/blink-dev/beforematch%7Csort:date/blink-dev/QKUZ_ALJdM8/j6daEdmUAgAJ >>> Intent to Experiment: >>> https://groups.google.com/a/chromium.org/d/msg/blink-dev/aTrk7__Eiq4/BOGSzGHeAwAJ >>> >>> >>> This intent message was generated by Chrome Platform Status >>> <https://chromestatus.com/>. >>> >> -- >> >> You received this message because you are subscribed to the Google Groups >> "blink-dev" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> >> To view this discussion on the web visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/5930d990-4a7c-4dea-8952-23bcb7d68e8dn%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/5930d990-4a7c-4dea-8952-23bcb7d68e8dn%40chromium.org?utm_medium=email&utm_source=footer> >> . >> >> -- > You received this message because you are subscribed to the Google Groups > "blink-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/3c0f15c2-ed6a-460e-b309-a5e9b198239fn%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/3c0f15c2-ed6a-460e-b309-a5e9b198239fn%40chromium.org?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADsXd2M1OzOo2Bh8mzcj35SL4tyFBvNtNn4nCWCX3oLTeN_hZg%40mail.gmail.com.
