SPA detected but no soft-navigation INP tracking (early-2026 standard, <5% adoption)

Your site is a single-page app, but it is not yet using the new browser method (soft-navigation tracking) for measuring responsiveness as users move between views. This is an early-2026 standard with low adoption so far. Without it you are partly blind to how snappy your app feels on real page-to-page navigation — the metric Google is moving toward. Early adopters get a measurement and ranking edge before it goes mainstream. Wire up the web-vitals library (v4+) with onINP() and a PerformanceObserver for soft-navigation entries, and send the data to your analytics. It is free and roughly a 30-minute job for a developer.