INP Doctor

Measure & fix Interaction to Next Paint (INP) with safe, reversible optimizations.

Description

INP Doctor helps you diagnose and reduce Interaction to Next Paint (INP) delays safely:

• Local RUM (anonymous) with INP attribution
• “Top Offenders” dashboard with URL/selector drill-down + CSV export
• Safe fixes: passive listeners, content-visibility for offscreen, viewport meta guard
• Script defer presets (conservative, dependency-aware)
• Speculative Loading (WP 6.8+): same-origin link prefetch on hover/viewport (no prerender)

Privacy: by default, data stays on your site. No cookies, no IPs, and no external telemetry.

Pro adds per-handle/per-selector controls, analytics worker offloading presets, and advanced Speculation UI.
Small notice only: see the footer link in plugin screens.

Installation

1. Upload the inp-doctor folder to /wp-content/plugins/, or install via Plugins → Add New.
2. Activate INP Doctor.
3. Visit INP Doctor → Top Offenders to see data (as traffic accrues).
4. Optional: enable Speculative Loading (WP 6.8+) and Safe Fixes toggles.

Frequently Asked Questions

Does this send data anywhere?

No. All RUM events are stored locally in your database (30-day retention). No cookies, no IP addresses.

Which WordPress/PHP versions are supported?

WordPress 6.3+ and PHP 8.0+. Speculation Rules require WordPress 6.8+.

Is it safe to enable the “Script defer (presets)” toggle?

Yes. It uses a conservative denylist and respects dependencies, admin bar, and scripts already marked async/defer/module.

Screenshots

1. Top Offenders with p75, average, worst, events, and example URL
2. Safe Fixes toggles (passive, content-visibility, viewport, defer presets)
3. Speculative Loading settings (excludes with simple patterns)

Changelog

1.0.0

Initial release.

Upgrade Notice

1.0.0

First public release: RUM + Top Offenders + Safe Fixes + Speculation (prefetch).