Chrome 146 extends Speculation Rules to support form submission — the browser can prerender the results page as the user types, so navigation is instant on submit. Experiment with the threshold, see the prerender log, and compare v146 vs pre-v146 rules.
Type a query of sufficient length to trigger prerender
Search Form
This form targets /results?q=…. As you type, a Speculation Rule triggers prerender of the target URL once the query reaches the confidence threshold. Watch the log below.
3
Prerender Log
No events yet — type in the search form above.
Timing Comparison
Submit the form twice — once with prerender active (green button) and once without — to compare navigation delta.
With prerender
—
Without prerender
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Delta saved
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Speculation Rules — Before vs After v146
Chrome 146 — form submission speculation rule
pre-v146 — hover-based only, no form support
<script type="speculationrules">
{
"prerender": [{
"where": {
"href_matches": "/results/*"
},
"eagerness": "moderate"
}]
}
</script>
// Problem: this fires on hover over ANY link to /results/*
// It cannot anticipate form submissions or use query value.
// The results page prerendered may not match what the user submits.
Live Injected Speculation Rule
The rule below is dynamically injected into the page as you type. It targets the specific URL the form would navigate to.