v151 · performance · prerendering

Speculation Rules: form_submission field

Extends speculation rules to support form-submission-triggered prerendering. Developers can instruct the browser to prepare a page as a form submission, so it activates instantly when the user submits the form.

concepts

  1. Syntax Builder

    Interactive builder for speculation rules JSON with the form_submission field. Configure URLs and conditions, then copy the generated rules.

  2. Feature Detection

    Probe whether the browser supports speculation rules, the form_submission field, and inspect any active prerender entries.

references

implementation reference

Need the exact API surface, compatibility boundaries, errors, lifecycle, and source links? Read the matching gendn reference ↗