Thanks for the review, Alex! No existing Range-producing APIs are modified. OpaqueRange is a new type created only via the new createValueRange() method. It extends AbstractRange rather than Range, so existing APIs are unaffected.
We’d like to validate the API shape with developers first, particularly the value-offset model for real use cases like inline suggestions and highlights. We don’t have specific partners lined up today, but we plan to reach out to potential partners during the experiment and hope to learn from interested developers as well. From: Alex Russell <[email protected]> Sent: Monday, March 23, 2026 11:44 AM To: blink-dev <[email protected]> Cc: Stephanie Zhang <[email protected]> Subject: [EXTERNAL] Re: Intent to Experiment: OpaqueRange You don't often get email from [email protected]<mailto:[email protected]>. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> First, thanks for the thorough and code-focused Explainer; nicely done. Are any of the existing Range-producing APIs modified here? I.e., do they now return OpaqueRange objects rather than (transparent) Range responses if, e.g., they happen to include an <input>? Also, are there any reasons not to ship now? E.g., are there partners lined up waiting to try OpaqueRange that we can learn from? Regardless, LGTM1 to experiment for 3 releases. On Monday, March 23, 2026 at 11:29:56 AM UTC-7 Stephanie Zhang wrote: Contact emails [email protected]<mailto:[email protected]>, [email protected]<mailto:[email protected]>, [email protected]<mailto:[email protected]>, [email protected]<mailto:[email protected]> Explainer https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/OpaqueRange/explainer.md Specification https://github.com/whatwg/dom/pull/1404 Summary OpaqueRange represents a live span of text within a form control’s value (for example, a <textarea> or text <input>), so developers can work with value text using range-like APIs. It enables operations like getBoundingClientRect(), getClientRects(), and use with the CSS Highlights API for UI such as inline suggestions, highlights, and anchored popovers. It preserves encapsulation by exposing only value offsets (and returning null for startContainer/endContainer), so DOM endpoints and internal structure aren’t exposed. Blink component Blink>DOM<https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EDOM%22> Web Feature ID Missing feature New feature ID for OpaqueRange · Issue #3863 · web-platform-dx/web-features<https://github.com/web-platform-dx/web-features/issues/3863> TAG review https://github.com/w3ctag/design-reviews/issues/1206 TAG review status Pending Goals for experimentation Validate API design and gather developer feedback on whether the API meets their needs. Risks Interoperability and Compatibility OpaqueRange adds new methods (e.g., createValueRange()) to <textarea> and text <input> elements so authors can create ranges over value text. It doesn’t change existing editing or selection behavior, so the risk to existing sites is low. The main interoperability risk is lack of implementation across engines, which could make text-anchored UI or highlights inside native controls work in only some browsers. Gecko: No signal (https://github.com/mozilla/standards-positions/issues/1289) WebKit: No signal (https://github.com/WebKit/standards-positions/issues/541) Web developers: Positive (https://github.com/w3c/csswg-drafts/issues/10346) Another positive example: https://github.com/whatwg/html/issues/11478 Other signals: Ergonomics OpaqueRange is typically used with selection offsets and with geometry/highlighting APIs. The geometry calls are synchronous and can trigger layout, similar to existing Range geometry methods. Since the range is live, offsets are updated as the control’s value is edited. Activation Moderate. Developers need to learn the value-offset model and how it differs from Range (there are no DOM endpoints). Security No new data exposure beyond existing access to form control values and selection. Exposes only value offsets and geometry and does not expose internal DOM (startContainer/endContainer are null). 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? Low. OpaqueRange adds a new method to <textarea> and text <input> elements, but does not change or deprecate any existing behavior Ongoing technical constraints None Debuggability No DevTools changes required. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)? Yes Works on all platforms that support <input> and <textarea> elements. Is this feature fully tested by web-platform-tests<https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>? Yes https://wpt.fyi/results/dom/ranges/tentative?label=experimental&label=master&aligned Flag name on about://flags N/A Finch feature name OpaqueRange Requires code in //chrome? False Tracking bug https://issues.chromium.org/issues/421421332 Measurement UseCounter `OpaqueRange` measures successful creation of OpaqueRange objects on <textarea> and text <input> elements. Estimated milestones Origin trial desktop first 148 DevTrial on desktop 148 Origin trial Android first 148 DevTrial on Android 148 Link to entry on the Chrome Platform Status https://chromestatus.com/feature/6297362687066112?gate=5151419728134144 Links to previous Intent discussions Intent to Prototype: https://groups.google.com/a/chromium.org/d/msgid/blink-dev/LV9PR21MB5189A114B34C8A3685A3C4A4805CA%40LV9PR21MB5189.namprd21.prod.outlook.com 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 visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CH3PR00MB26119B282B3576D0DE08F3B8EC48A%40CH3PR00MB2611.namprd00.prod.outlook.com.
