Yes, it only works for GET based form submissions. On Wednesday, June 10, 2026 at 10:45:42 PM UTC+9 Yoav Weiss wrote:
> On Tuesday, June 9, 2026 at 6:22:10 AM UTC+2 Chromestatus wrote: > > *Contact emails* > [email protected] > > *Explainer* > https://github.com/WICG/nav-speculation/blob/main/ > prerendering-form-submission.md > > > Am I correct to assume that this only works for GET based form submissions? > > > > > *Specification* > https://storage.googleapis.com/spec-previews/WICG/nav- > speculation/pull/426/diff/prerendering.html > > *Design docs* > > https://docs.google.com/document/d/13Xr_kSYZtvhRNaKpCiP7wLKYtDcpLdDWSH > 4y6gHq0kQ/edit?usp=sharing > > *Summary* > This extends speculation rules syntax to allow developers to specify the > form_submission field for prerender. This field directs the browser to > prepare the prerender as a form submission, so that it can be activated by > real form submission navigations. Examples include a simple search form > which results in a /search?q=XXX GET request navigation, support of which > has been requested by web developers. > > *Blink component* > Internals>Preload>Prerender > <https://issues.chromium.org/issues?q=customfield1222907:%22Internals%3EPreload%3EPrerender%22> > > *Web Feature ID* > speculation-rules <https://webstatus.dev/features/speculation-rules> > > *Motivation* > Form submissions cannot activate prerendered pages currently by design, > due to internal browser limitations. In at least Chrome, ordinary form > submission navigations have special state and run extra checks that > ordinary prerenders don't experience. This means that a form submission can > never activate a prerender, because the prerender was not prepared properly > as a form submission. In addition to the internal browser limitations, > resources can be wasted on prerendering a page which is not eligible, such > as CSP disallowing form-action. > > *Initial public proposal* > https://github.com/WICG/nav-speculation/issues/322 > > *TAG review* > https://github.com/w3ctag/design-reviews/issues/1192 > > *TAG review status* > Issues addressed > > *Origin Trial Name* > PrerenderActivationByFormSubmission > > *Goals for experimentation* > To evaluate how the prerendering form_submission support works on real > sites before shipping it by default. We will be evaluating performance, > stability, and correctness, and any other feedback the sites have when they > use this feature. > > *Chromium Trial Name* > PrerenderActivationByFormSubmission > > *Origin Trial documentation link* > https://github.com/WICG/nav-speculation/blob/main/ > prerendering-form-submission.md > > *WebFeature UseCounter name* > kPrerenderActivationByFormSubmission > > *Risks* > > > *Interoperability and Compatibility* > The entire speculative loading feature is a progressive enhancement, so in > general risks are low in this area. > > *Gecko*: No signal (https://github.com/mozilla/standards-positions/ > issues/1355) Mozilla is neutral on speculation rules syntax in general ( > https://github.com/mozilla/standards-positions/issues/620), although > positive on prefetching. This new request for this specific feature is > still pending for new response after pinging. > > *WebKit*: No signal (https://github.com/WebKit/standards-positions/ > issues/614) WebKit has not yet responded to our 2022 request for a > position on speculation rules although positive on same-origin prefetching. > (https://github.com/WebKit/standards-positions/issues/54) We opened a new > request for this specific feature to ensure we captured any of their input. > > *Web developers*: Positive (https://github.com/ > WICG/nav-speculation/issues/322) > > *Other signals*: > > *Ergonomics* > No > > *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? > None, speculation rules prerender are not supported on WebView. > > > *Debuggability* > As well as other speculationrule features, this feature can be viewed on > devtools as the source script. Another dedicated field will be added to the > panel for easier debugging. > > *Will this feature be supported on all six Blink platforms (Windows, Mac, > Linux, ChromeOS, Android, and Android WebView)?* > No > Windows, Mac, Linux, ChromeOS, Android. WebView doesn't support > speculation rules prerendering because prerendering navigation breaks the > lifecycle (e.g., callback sequence) of the WebView. > > *Is this feature fully tested by web-platform-tests > <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?* > Yes > > > *Flag name on about://flags* > PrerenderActivationByFormSubmission > > *Finch feature name* > PrerenderActivationByFormSubmission > > *Rollout plan* > Will ship enabled for all users > > *Requires code in //chrome?* > False > > *Tracking bug* > https://issues.chromium.org/issues/346555939 > > *Measurement* > Blink.UseCounter.Features https://crrev.com/c/7533307 > > *Estimated milestones* > Shipping on desktop151 Origin trial desktop first146 Origin trial desktop > last151 DevTrial on desktop146 Shipping on Android151 Origin trial > Android first146 Origin trial Android last151 DevTrial on Android146 > > *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). > None. > > *Link to entry on the Chrome Platform Status* > https://chromestatus.com/feature/5074313831120896?gate=6571193366872064 > > *Links to previous Intent discussions* > Intent to Prototype: https://groups.google.com/a/ > chromium.org/d/msgid/blink-dev/698f0243.2b0a0220.19817b. > 0194.GAE%40google.com > Intent to Experiment: https://groups.google.com/a/ > chromium.org/d/msgid/blink-dev/69aa2f3b.2b0a0220.c2d7. > 0503.GAE%40google.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]. 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