Thanks Vlad and Mike! Replies inline.
On Tue, May 19, 2026 at 10:47 AM Vladimir Levin <[email protected]> wrote: > > > On Mon, May 18, 2026 at 5:55 PM Mike Taylor <[email protected]> > wrote: > >> On 5/18/26 4:11 p.m., Florin Malita wrote: >> >> *Contact emails* >> [email protected], [email protected], [email protected], >> [email protected] >> >> *Explainer* >> https://github.com/fserb/canvas2D/blob/master/spec/enhanced-textmetrics.md >> >> https://github.com/Igalia/explainers/blob/main/canvas-formatted-text/text-metrics-additions.md >> https://github.com/whatwg/html/issues/10677 >> >> *Specification* >> https://github.com/whatwg/html/pull/11000 >> >> *Summary* >> Expand the TextMetrics Canvas API to support selection rectangles, >> bounding box queries, and glyph cluster-based operations. This new >> functionality should enable complex text editing applications with accurate >> selection, caret positioning, and hit testing. Additionally, cluster-based >> rendering facilitates sophisticated text effects such as independent >> character animations and styling. >> >> *Blink component* >> Blink>Canvas >> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ECanvas%22> >> >> *Web Feature ID* >> *No information provided* >> >> *TAG review* >> https://github.com/w3ctag/design-reviews/issues/1095 >> >> *TAG review status* >> Pending >> >> *Origin Trial Name* >> Enhanced Canvas TextMetrics >> >> *Goals for experimentation* >> Partners have implemented prototypes based on the available runtime >> feature, with positive feedback. They are now interested in expanding the >> scope, and testing the API with real users. This experiment will provide >> valuable validation in real-world use scenarios, and should help us gauge >> the proposed API's fitness, ergonomics, and performance. >> >> Can you also comment on progress in the following areas? >> >> Draft spec (early draft is ok, but must be spec-like and associated with >> the appropriate standardization venue, or WICG) >> > Just to add to Mike's question here, the last activity on this HTML PR > https://github.com/whatwg/html/pull/11000 seems to be from roughly a year > ago. Is this still under active discussion? (Similar activity on > https://github.com/whatwg/html/issues/10677) > The spec PR needs a couple of minor updates based on TAG feedback. Beyond that, it is pending review and agreement on https://github.com/whatwg/html/issues/10677. The main friction point is the proposal <https://github.com/whatwg/html/issues/10677#issuecomment-2787797845> to significantly increase scope by exposing intermediate text shaping stages and related info. We maintain that this is non-critical for current use cases and can be deferred. schenney@ is engaging with Apple engineers to reach a resolution. > TAG review (see exceptions) >> > The TAG review offered some great feedback. One major focus was accessibility, where the group’s position is to encourage more accessible alternatives instead of expanding canvas APIs (which are generally lacking). We discussed several alternatives, but unfortunately none of them fulfill the low-level requirements we set to solve with TextClusters. The upcoming HTML-in-Canvas should address some of the general Canvas accessibility issues, and is a good complement to Enhanced TextMetrics (an incremental Canvas API extension focusing on low-level text rendering capabilities). Tangentially, TAG and WHATWG feedback also led to the implementation of language and text writing mode support for Canvas, which is tracked through separate intents. > signals requests >> > Apple engineers were involved in the initial discussions. schenney@ is reaching out to re-engage. Outreach for feedback from the spec community >> > Feedback has been collected primarily through the spec PR and associated discussions. Notably, Igalia/schenney@ have published blog posts and explainers to socialise the proposal: https://blogs.igalia.com/schenney/canvas-text-editing/ https://github.com/Igalia/explainers/blob/main/canvas-formatted-text/text-metrics-additions.md > WPT tests >> > WPT tests have been merged upstream as 'tentative' pending the finalization of the spec: https://wpt.fyi/results/html/canvas/offscreen/text?label=master&label=experimental&aligned&q=tentative > >> *Chromium Trial Name* >> ExtendedTextMetrics >> >> *Origin Trial documentation link* >> >> https://github.com/Igalia/explainers/blob/main/canvas-formatted-text/text-metrics-additions.md >> >> *WebFeature UseCounter name* >> kExtendedTextMetrics >> >> *Risks* >> >> >> *Interoperability and Compatibility* >> These are new features and we will get vendor agreement at WHATWG before >> shipping. So minimal interop risks beyond platform-specific metrics >> differences. >> >> *Gecko*: No signal ( >> https://github.com/mozilla/standards-positions/issues/1144) >> >> *WebKit*: No signal ( >> https://github.com/WebKit/standards-positions/issues/436) >> >> *Web developers*: Positive Developers want the ability to animated >> glyphs independendly (such as exploding sentences) and the ability to do >> e.g. selection on canvas text. The proposed APIs support these use cases >> and more. >> >> *Other signals*: >> >> *Ergonomics* >> None. >> >> *Activation* >> None. >> >> *Security* >> There is always a fingerprinting concern with HTML canvas. THe new >> features expose no novel fingerprinting surface (text metrics are already a >> fingerprinting concern). >> >> *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 information provided* >> >> >> *Reason this experiment is being extended* >> Flutter Web has provided positive initial feedback based on internal >> testing. To validate the feature at scale, they require additional time to >> expose it to external developers via their own experimentation >> infrastructure. >> >> The goal of this extension is to gather telemetry and feedback from >> real-world applications, allowing us to identify and address any remaining >> rough edges before proceeding with a formal launch. >> >> *Ongoing technical constraints* >> *No information provided* >> >> *Debuggability* >> DevTools supports querying the APIs by default. >> >> *Will this feature be supported on all six Blink platforms (Windows, Mac, >> Linux, ChromeOS, Android, and Android WebView)?* >> Yes >> >> *Is this feature fully tested by web-platform-tests >> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?* >> Yes >> html/canvas/[element|offscreen]/text... >> 2d.text.measure.index-from-offset* 2d.text.measure.selection-rects* >> 2d.text.measure.text-clusters* >> https://wpt.fyi/results/html/canvas/element/text?label=master&label=experimental&aligned&q=tentative >> >> https://wpt.fyi/results/html/canvas/offscreen/text?label=master&label=experimental&aligned&q=tentative >> >> I see there are some tests that pass in all browsers - that suggests the >> test isn't working as intended? >> >> e.g., >> https://wpt.fyi/results/html/canvas/offscreen/text/2d.text.measure.strokeTextCluster-font-change.tentative.html?label=master&label=experimental&aligned&q=tentative >> > Thanks, agreed, that's unexpected. I filed a bug <https://issues.chromium.org/issues/514632337> to investigate. > >> *Flag name on about://flags* >> Experimental Web Platform Features >> >> *Finch feature name* >> ExtendedTextMetrics >> >> *Requires code in //chrome?* >> False >> >> *Tracking bug* >> https://issues.chromium.org/issues/341213359 >> >> *Measurement* >> UMA counters will be added for the new APIs. >> >> *Estimated milestones* >> Origin trial desktop first 144 >> Origin trial desktop last 149 >> Origin trial extension 1 end milestone 155 >> DevTrial on desktop 141 >> Origin trial Android first 144 >> Origin trial Android last 149 >> DevTrial on Android 141 >> >> *Link to entry on the Chrome Platform Status* >> https://chromestatus.com/feature/5075532483657728?gate=5178855770947584 >> >> *Links to previous Intent discussions* >> Intent to Prototype: >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADgYMVdqo4PBs4OkGqVncRizs8vtX4YtFLDcK%2BRxdYo_wnaRJQ%40mail.gmail.com >> Ready for Trial: >> https://groups.google.com/a/chromium.org/g/blink-dev/c/OLCCI0ExvIk >> Intent to Experiment: >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADgYMVfC-Naw8pFVaUUPMSfW-u3kC7SMdDeHJgwU5YmSHOOeeA%40mail.gmail.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/CADgYMVfjd5mbDkm16_Xf4fxfnrEeiAXLhjiBCXWik0GaNJGE2Q%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADgYMVfjd5mbDkm16_Xf4fxfnrEeiAXLhjiBCXWik0GaNJGE2Q%40mail.gmail.com?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/7942727a-4657-40c4-95c3-172fcab90271%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/7942727a-4657-40c4-95c3-172fcab90271%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/CADsXd2PQiHFe0teA%2BAZ6TLOB86CMCE5h6qpVvQ8_jEL3u%3Do99w%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADsXd2PQiHFe0teA%2BAZ6TLOB86CMCE5h6qpVvQ8_jEL3u%3Do99w%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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