🎤 2. Configuration Reference

This document provides a comprehensive overview of all settings available for the JaJuMa Page Preload extension.
The configurations allow for precise control over preloading behavior, enabling a tailored performance strategy that balances speed improvements with server resource consumption.

👉 2.1 Accessing the Configuration

All settings for the extension can be found in the Magento Admin Panel by navigating to:
JaJuMa > Page Preload

The configuration is divided into four main sections:

• General Settings,
• Preload Intensity,
• Preload Scope, and
• Preload Cache Control.

🔜 2.2 General Settings

This section contains the master switches for the extension's functionality.

• Enable Extension: A Yes/No dropdown to enable or disable the extension globally.

  • Yes: Enables page preloading according to the configured settings below.
  • No: Completely disables the extension's script from being added to the frontend.

• Only Use Page Preload for Browsers Without Speculation Rules API Support: A Yes/No dropdown.

  • Yes: Enables page preloading only for Browsers without Speculation Rules API Support.
  • No: Enables page preloading only for all Browsers.

  --> Why it matters:
  This setting allows you to create a sophisticated hybrid performance strategy.
  When enabled, Page Preload will only be active on browsers that don't support the modern Speculation Rules API (like Firefox and Safari). This ensures all users get a speed boost, while allowing you to use more advanced prerendering techniques for users on Chromium browsers.

Recommendation:
For Chromium-based browsers (Chrome, Edge, etc.), we recommend using a dedicated Smart Speculation Rules extension for better performance and reduced server load, or using both, Speculation Rules AND Page Preload together for maximum performance impact.

💡 Pro Tip:
Before enabling the extension in a production environment, it is highly recommended to review and configure the Preload Intensity and Preload Scope sections to prevent unintended preloading of sensitive pages or excessive server load.

🏁 2.3 Preload Intensity: Fine-Tuning Your Strategy

The Preload Intensity setting defines the user action that triggers a preloading event.

Following options are available:

1. On Hover + 65ms (Default):
   Links will be preloaded 65 ms after hovering a link and when a mobile user starts touching their display.
2. On Hover + Custom Delay:
   Links will be preloaded with custom delay as configured after hovering a link and when a mobile user starts touching their display. A lower value means more preload requests, a higher value will reduce the preload requests.
3. On Mousedown (Desktop Only):
   Links will be preloaded when the user starts pressing their mouse button, right before releasing it. Links are only preloaded on Desktop, but not on mobile devices.
4. On Mousedown:
   Links will be preloaded when the user starts pressing their mouse button, right before releasing it.
5. When Visible (Mobile only):
   Links will be preloaded as soon as they’re visible on Mobile Devices. On Desktop Default will be used.
6. When Visible:
   Links will be preloaded as soon as they’re visible. On both, Desktop and Mobile Devices.

The design of these options deliberately mirrors the trade-offs found in the modern Speculation Rules API's eagerness property.
By choosing an intensity level, you are effectively selecting a preloading strategy that aligns with industry best practices for balancing performance gains against resource costs.

2.3.1 The “Cautious” Strategy (On Mousedown)

• Options: On Mousedown (Desktop Only), On Mousedown
• Why it matters:
  This strategy initiates a preload only when the user presses their mouse button on a link.
  This is a high-confidence signal that a navigation is about to occur.
  It results in virtually no wasted requests, making it a very safe option that avoids any unnecessary load on your server while still improving page loads by around 80ms on average.

2.3.2 The “Balanced” Strategy (On Hover)

• Options: On Hover + 65ms (Default), On Hover + Custom Delay
• Why it matters:
  This is the recommended default strategy for most stores.
  It preloads a page shortly after a user hovers their mouse over a link, providing a substantial performance improvement of up to several hundred milliseconds.
  This strategy may create some unused requests, so it is strongly recommended to use this option with a Full Page Cache (like Varnish) and a well-defined Preload Scope.

2.3.3 The “All-In” Strategy (When Visible)

• Options: When Visible (Mobile only), When Visible
• Why it matters:
  This is the most aggressive strategy, designed for maximum performance impact.
  It preloads links as soon as they become visible in the user's viewport, making navigations feel truly instant.
  However, this approach can generate a significant number of unused requests and place a heavy load on the server.
  It should only be used with care or on high-capacity infrastructure with Varnish enabled and a very strict Whitelist.

🛡 2.4 Preload Scope: Whitelists and Blacklists

This section is a critical safety and optimization feature.
It allows you to define exactly which links are eligible for preloading.

⚠ Warning:
Any preloading technology, including the Speculation Rules API, carries the risk of triggering unintended actions if not properly controlled.
For instance, preloading a /customer/account/logout link could inadvertently log a user out.
The Preload Scope configuration is the primary mechanism to mitigate these risks.

• Blacklist:
  The extension will preload any link on the site except for those whose URLs match the provided patterns.
  This is the recommended minimum configuration for safety.
• Whitelist:
  The extension will only preload links whose URLs match the provided patterns.
  This is the safest and most controlled method, especially when using the "All-In" intensity strategy.

2.4.1 Critical URLs to Blacklist

It is essential to prevent the preloading of any link that triggers a state-changing action. A robust blacklist should be configured as a baseline safety measure.

Recommended Blacklist Patterns:
/checkout/cart/add, add_to_cart, /wishlist/, /customer/, /checkout/, /cart/, /logout, /login, switcher.

🕑 2.5 Preload Cache Control

This section controls the caching behavior of preloaded pages on the end-user's browser.

• Preloaded Content TTL (Time-To-Live):
  This setting, in seconds, determines how long a user's browser should keep a prefetched page in its local memory cache.
  The default is 300 seconds (5 minutes).

--> Why it matters:
The TTL should be long enough to ensure the page is still cached when the user clicks, but not so long that it increases the risk of serving stale content (e.g., outdated stock levels).

📞 Need Help?

Still have questions or need help with your configuration? Our expert team is here to assist. Please don't hesitate to contact our support team for personalized assistance.