Oxyplug Prefetch & Prerender

Faster next-page loads by prefetching and prerendering links using the browser's native Speculation Rules API. It improves perceived performance, UX, and Core Web Vitals.

⚠️ Speculation Rules are supported only on Chromium-based browsers (v121+). Other browsers simply ignore the rules — no errors, no fallback needed.

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Features

• Immediate prefetch — automatically prefetch the first N items on post/product/category listing pages (default 4, configurable).
• Immediate prerender — fully prerender the first N listing items, like an invisible background tab (default 3, configurable).
• Hover (moderate) prefetch/prerender — speculate a destination when the user hovers a link, just before the click.
• Per-post custom URLs — specify exact URLs to prefetch/prerender from a given post, product, or page via a metabox.
• Exclusions — skip URLs by path, with RegEx-style href_matches patterns for hover mode, plus a selector_matches CSS opt-out (.no-prefetch / .no-prerender / rel="nofollow").
• Safe by default — state-changing GET links (login, admin, comments, checkout/my-account, add-to-cart, nonce-bearing URLs) are excluded out of the box.
• WordPress 6.8 core-aware — integrates with core Speculative Loading and suppresses core's block when active to avoid duplicate rules.
• No-Vary-Search — one entry can match URLs differing only by tracking/sort query params.
• Configurable eagerness — conservative / moderate / eager per feature.

Prefetch vs. Prerender

	What it does	Cost	Best for
Prefetch	Downloads the next page's document only	Low	Broad coverage of likely-next links
Prerender	Fully renders the next page in the background	Higher	A small number of very-likely next pages

Requirements

• WordPress 5.3+
• PHP 7.4+
• A Chromium-based browser (v121+) on the visitor side to benefit from speculation

Installation

From source

1. Download or clone this repository into your wp-content/plugins/ directory:

   git clone https://github.com/Oxyplug/oxy-prefetch.git wp-content/plugins/oxyplug-prefetch

2. Activate Oxyplug Prefetch & Prerender from the WordPress Plugins screen.
3. Configure under Tools → Oxyplug Prefetch & Prerender.

Building the admin assets (optional)

The Material Design 3 admin components are bundled in assets/js/dist/. To rebuild them:

npm install
npm run build

Usage

1. Go to Tools → Oxyplug Prefetch & Prerender.
2. Enable and tune:
   • Prefetch — number of immediate prefetches, and/or hover prefetch.
   • Prerender — number of immediate prerenders, and/or hover prerender.
   • Exclusion — paths to skip (RegEx allowed for hover mode).
3. On any post/page/product edit screen, use the Oxyplug Prefetch & Prerender metabox to add custom URLs to prefetch/prerender when that page is viewed.

Exclusion examples

Pattern	Effect
/logout	Excludes the logout path
/(page1|page2)/	Excludes URLs starting with page1 or page2
/custom_pages/*	Excludes anything under custom_pages

How it works

On the front end the plugin emits one or more <script type="speculationrules"> blocks in the footer:

• Immediate rules use a list source built from the current query's first N permalinks (and any per-post custom URLs).
• Moderate rules use a document source with a configurable eagerness, matching /* and excluding the configured paths and state-changing links via not → href_matches / not → selector_matches, with optional expects_no_vary_search.

On WordPress 6.8+, the plugin detects core's own Speculative Loading: it feeds its default exclusions into core and, when any of its features are enabled, suppresses core's block so the page never ships two competing rule sets.

Development

• Main plugin logic: oxy-prefetch.php
• Admin script: assets/js/admin-script.js
• Block-editor integration: assets/js/gutenberg-script.js
• MD3 components: assets/js/src/ → built to assets/js/dist/ with Vite

Lint locally:

php -l oxy-prefetch.php
node --check assets/js/admin-script.js

Changelog

See readme.txt for the full changelog. Latest:

3.1.0

• Integrate with WordPress core Speculative Loading (WP 6.8+): feed default exclusions into core and suppress core output when the plugin's features are active, to avoid duplicate/competing rule sets
• Add No-Vary-Search support so prefetch/prerender entries still match URLs that differ only by tracking/sort query params (configurable param list)
• Make eagerness (conservative / moderate / eager) configurable per feature for prefetch and prerender
• Broaden default exclusions to protect state-changing GET links (wp-login.php, wp-admin, comments, checkout/my-account, add-to-cart, remove_item, undo_item, _wpnonce, _wp_http_referer)
• Add CSS opt-out via selector_matches (.no-prefetch / .no-prerender / .no-speculation and rel="nofollow")
• Add a prerender + analytics caveat note in the settings UI
• Add oxy_prefetch_immediate_rules / oxy_prefetch_moderate_rules filters (e.g. to deliver rules via the Speculation-Rules HTTP header) and exclusion filters
• Tested up to WordPress 6.8

3.0.2

• Add str_starts_with() polyfill for PHP 7.4 compatibility
• Fix same-host validation for custom prefetch/prerender URLs
• Add capability checks to settings and notice AJAX handlers
• Use wp_update_post() instead of direct DB writes
• Add uninstall cleanup of options, transients, and post meta
• Load admin assets only on relevant screens
• Tested up to WordPress 7.0

Links

• 🌐 Product page
• 📖 Documentation

License

GPLv2 or later — © Oxyplug