How to Enable Selective Media Preload in WordPress

Why You Need It

Preloading all media wastes bandwidth. Selective preloading targets only the media that matters most (hero images, above-the-fold content).

How to Enable this Feature

Step 1: Navigate to Settings

Click into the Classic Monks plugin settings, then the Performance tab, Monks Preloading subtab.

Step 2: Enable the Feature

Toggle on the feature.

Step 3: Save and Test

Click Save Changes. Test on the frontend.

Common Use Cases

Hero sections

Preload only the hero image, not all images on the page.

Featured content

Preload the featured image or video, not all media on the page.

Troubleshooting

The feature is not taking effect

Cause: The toggle is off, or a caching plugin is serving the old page.
Fix: Verify the toggle is on. Clear all caching layers.

The feature breaks another plugin

Cause: Another plugin depends on the functionality that this feature disables.
Fix: Disable this feature if it breaks another plugin.

Developer integration

This feature registers 4 WordPress hooks in selective-media-preload.php:

Actions:

• add_meta_boxes calls cm_add_selective_media_preload_metabox() (Adds preload metabox to enabled post types)
• save_post calls cm_save_selective_media_preload_data() (Saves per-post preload media data)
• wp_head calls cm_output_selective_media_preload_tags() (Outputs link preload tags (priority 1))

Filters:

• wp_img_tag_add_loading_attr calls cm_selective_media_prevent_lazy_loading() (Prevents lazy loading for preloaded images (priority 10))

// Hooked in selective-media-preload.php
add_action( 'add_meta_boxes', 'cm_add_selective_media_preload_metabox' );

The feature modifies WordPress behavior by registering or removing hooks. Disabling it reverses those changes and WordPress returns to its default behavior.

Before you enable this feature

1. Test on staging first to verify no conflicts with your theme or other plugins
2. Check dependent plugins that may rely on the functionality being modified
3. Monitor after enabling for any unexpected behavior on the frontend

How it works under the feature

This feature runs during the WordPress initialization phase. When enabled, its PHP code registers hooks that modify specific WordPress behaviors. The changes are non-destructive and reversible.

No database schema changes are made. The feature state is stored as a boolean value in the wp_options table and can be toggled at any time from the admin settings.