Intent to Prototype: Speculation rules: form_submission field

[Chromestatus]

Contact emails

robe...@chromium.org

Explainer

https://github.com/WICG/nav-speculation/blob/main/prerendering-form-submission.md

Specification

https://wicg.github.io/nav-speculation/prerendering.html

Design docs

https://docs.google.com/document/d/13Xr_kSYZtvhRNaKpCiP7wLKYtDcpLdDWSH4y6gHq0kQ/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

Web Feature ID

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

Requires code in //chrome?

False

Tracking bug

https://issues.chromium.org/issues/346555939

Measurement

Blink.UseCounter.Features

Estimated milestones

DevTrial on desktop	146
DevTrial on Android	146

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/5074313831120896?gate=5203276750520320

This intent message was generated by Chrome Platform Status.