LGTM2 On 5/18/26 2:44 p.m., Alex Russell wrote:
LGTM1On Monday, May 18, 2026 at 5:39:00 AM UTC-7 Shweta Bindal wrote: Hi @Vincent <mailto:[email protected]> This feature was shipped in 2019 by Safari. 203168 – [Clipboard API] Implement ClipboardItem.getType() for platform clipboard items <https://bugs.webkit.org/show_bug.cgi?id=203168> - this is the bug under which it was shipped. Regards, Shweta Bindal ------------------------------------------------------------------------ *From:* Vincent Scheib <[email protected]> *Sent:* Saturday, May 16, 2026 4:16 AM *To:* Shweta Bindal <[email protected]> *Cc:* blink-dev <[email protected]>; Rakesh Goulikar <[email protected]>; Rohan Raja <[email protected]>; ASHISH KUMAR <[email protected]> *Subject:* [EXTERNAL] Re: [blink-dev] Intent to Ship: Selective Clipboard Format Read You don't often get email from [email protected]. Learn why this is important <https://aka.ms/LearnAboutSenderIdentification> Looking forward to this, it seems a good optimization no web developer API change. How long has this been shipped in Safari? On Thu, May 14, 2026 at 1:03 AM 'Shweta Bindal' via blink-dev <[email protected]> wrote: *Contact emails* [email protected], [email protected] <mailto:[email protected]>, [email protected] <mailto:[email protected]> *Explainer* https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/ClipboardAPI/SelectiveClipboardFormatRead/explainer.md <https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/ClipboardAPI/SelectiveClipboardFormatRead/explainer.md> *Specification* https://github.com/w3c/clipboard-apis/pull/248 <https://github.com/w3c/clipboard-apis/pull/248> *Summary* Enhances the Asynchronous Clipboard API by deferring actual clipboard data retrieval from the OS until the web application calls getType(). Instead of eagerly fetching all available formats at read() time, the browser now returns ClipboardItem objects with available MIME types but without the underlying data, and reads from the OS clipboard only when getType() is invoked. const items = await navigator.clipboard.read(); // No data read yet const text = await items.getType('text/plain'); // Only 'text/plain' data read here This reduces CPU usage, improves the perceived responsiveness of the API call, and optimizes the browser's power consumption. *Blink component* Blink>DataTransfer <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EDataTransfer%22> *Web Feature ID* async-clipboard <https://webstatus.dev/features/async-clipboard> *Motivation* Currently, web applications can read clipboard content through the Async Clipboard API. However, the current implementation eagerly fetches all MIME types from the OS clipboard at read() time, regardless of which formats the application actually needs. This feature defers the actual data retrieval to getType() time, so the browser reads only the requested MIME types from the OS clipboard when they are needed, improving performance and reducing unnecessary data transfer. *Initial public proposal* https://github.com/WICG/proposals/issues/224 <https://github.com/WICG/proposals/issues/224> *TAG review* None requested because this behavior has achieved consensus in the Editing working group and matches what Safari already does *TAG review status* Not applicable *Goals for experimentation* NA *Risks* *Interoperability and Compatibility* /No information provided/ /Gecko/: Positive (https://github.com/mozilla/standards-positions/issues/1279 <https://github.com/mozilla/standards-positions/issues/1279>) /WebKit/: Shipped/Shipping (https://github.com/WebKit/standards-positions/issues/537 <https://github.com/WebKit/standards-positions/issues/537>) /Web developers/: Positive (https://github.com/WICG/proposals/issues/224 <https://github.com/WICG/proposals/issues/224>) Webkit has already implemented this behavior /Other signals/: *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 risks for WebView *Debuggability* No DevTools debugging support needed for this. *Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)?* Yes It is supported on all platforms because it is purely a browser-internal optimization that changes when existing OS clipboard APIs are called (deferring from read() time to getType() time), without requiring any new platform-specific clipboard capabilities or OS-level API changes. *Is this feature fully tested by **web-platform-tests* <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>*?* No Added initial tests to WPT, but further coverage is currently blocked by missing test infrastructure. Created an issue for that (https://issues.chromium.org/issues/508091414 <https://issues.chromium.org/issues/508091414>) *Flag name on about://flags* DeferOsClipboardReadCallToGetType *Finch feature name* /No information provided/ *Non-finch justification* As previously collected in UseCounters 5684 and 5685, telemetry tracking how often the clipboard changes between read and getType (or consecutive getType calls) shows an extremely low usage percentage (~0.0004). This data demonstrates that the risk of breaking existing workflows is negligible. Consequently, a Finch rollout is unnecessary. *Rollout plan* Will ship enabled for all users *Requires code in //chrome?* False *Tracking bug* https://issues.chromium.org/issues/435051711 <https://issues.chromium.org/issues/435051711> *Estimated milestones* Shipping on desktop 149 Shipping on Android 149 Shipping on WebView 149 Shipping on iOS 149 *Anticipated spec changes* /Open questions about a feature may be a source of future web compat or interop issues. Please list open issues (e.g. links to known github issues in the project for the feature specification) whose resolution may introduce web compat/interop risk (e.g., changing to naming or structure of the API in a non-backward-compatible way)./ N/A *Link to entry on the Chrome Platform Status* https://chromestatus.com/feature/5203433409871872?gate=6255790323269632 <https://chromestatus.com/feature/5203433409871872?gate=6255790323269632> This intent message was generated by Chrome Platform Status <https://chromestatus.com/>.-- You received this message because you are subscribed to theGoogle Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected] <mailto:[email protected]>. 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