Disable Unnecessary WordPress Features
Add these functions to your child theme’s functions.php file to remove features that may impact performance:
// Disable WordPress emoji scripts and styles
function digifusion_child_disable_emojis() {
remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
remove_action( 'wp_print_styles', 'print_emoji_styles' );
remove_action( 'admin_print_styles', 'print_emoji_styles' );
remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
remove_filter( 'comment_text_rss', 'wp_staticize_emoji' );
remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );
}
add_action( 'init', 'digifusion_child_disable_emojis' );
// Remove unnecessary WordPress head tags
function digifusion_child_cleanup_head() {
remove_action( 'wp_head', 'wp_generator' );
remove_action( 'wp_head', 'wp_shortlink_wp_head' );
remove_action( 'wp_head', 'wlwmanifest_link' );
remove_action( 'wp_head', 'rsd_link' );
remove_action( 'wp_head', 'adjacent_posts_rel_link_wp_head' );
}
add_action( 'init', 'digifusion_child_cleanup_head' );
// Disable WordPress heartbeat on frontend
function digifusion_child_disable_heartbeat() {
if ( ! is_admin() ) {
wp_deregister_script( 'heartbeat' );
}
}
add_action( 'wp_enqueue_scripts', 'digifusion_child_disable_heartbeat' );Optimize Asset Loading
Defer Non-Critical JavaScript
// Defer JavaScript loading for better performance
function digifusion_child_defer_scripts( $tag, $handle, $src ) {
// Scripts to defer (add more as needed)
$defer_scripts = array(
'digifusion-app',
'comment-reply',
'wp-embed'
);
if ( in_array( $handle, $defer_scripts ) ) {
return str_replace( ' src', ' defer src', $tag );
}
return $tag;
}
add_filter( 'script_loader_tag', 'digifusion_child_defer_scripts', 10, 3 );
// Preload critical assets
function digifusion_child_preload_assets() {
// Preload theme stylesheet
echo '<link rel="preload" href="' . get_stylesheet_uri() . '" as="style" onload="this.onload=null;this.rel=\'stylesheet\'">';
// Preload critical fonts
echo '<link rel="preload" href="' . get_stylesheet_directory_uri() . '/assets/fonts/primary-font.woff2" as="font" type="font/woff2" crossorigin>';
}
add_action( 'wp_head', 'digifusion_child_preload_assets', 1 );Database Query Optimization
// Limit post revisions
function digifusion_child_limit_revisions( $num, $post ) {
return 3;
}
add_filter( 'wp_revisions_to_keep', 'digifusion_child_limit_revisions', 10, 2 );
// Optimize database queries for widgets
function digifusion_child_optimize_widget_queries() {
// Disable widgets on non-widget areas to reduce queries
if ( ! is_active_sidebar( 'sidebar-1' ) && ! is_singular() ) {
remove_action( 'wp_head', '_wp_render_title_tag', 1 );
}
}
add_action( 'wp', 'digifusion_child_optimize_widget_queries' );
// Cache heavy queries
function digifusion_child_get_popular_posts( $limit = 5 ) {
$cache_key = 'digifusion_popular_posts_' . $limit;
$popular_posts = wp_cache_get( $cache_key );
if ( false === $popular_posts ) {
$popular_posts = get_posts( array(
'numberposts' => $limit,
'meta_key' => 'post_views_count',
'orderby' => 'meta_value_num',
'order' => 'DESC',
'post_status' => 'publish'
) );
wp_cache_set( $cache_key, $popular_posts, '', 3600 ); // Cache for 1 hour
}
return $popular_posts;
}Image Optimization
// Add SVG support
function digifusion_child_add_svg_support( $mime_types ) {
$mime_types['svg'] = 'image/svg+xml';
return $mime_types;
}
add_filter( 'upload_mimes', 'digifusion_child_add_svg_support' );
// Lazy load images
function digifusion_child_add_lazy_loading( $attr, $attachment, $size ) {
if ( ! is_admin() ) {
$attr['loading'] = 'lazy';
$attr['decoding'] = 'async';
}
return $attr;
}
add_filter( 'wp_get_attachment_image_attributes', 'digifusion_child_add_lazy_loading', 10, 3 );
// Optimize image sizes
function digifusion_child_custom_image_sizes() {
// Add optimized image sizes
add_image_size( 'optimized-thumbnail', 300, 200, true );
add_image_size( 'optimized-medium', 600, 400, true );
}
add_action( 'after_setup_theme', 'digifusion_child_custom_image_sizes' );Critical CSS Implementation
Create a file assets/css/critical.css in your child theme:
/* Critical above-the-fold styles */
body {
font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
line-height: 1.6;
margin: 0;
padding: 0;
}
.site-header {
position: relative;
z-index: 1000;
}
.site-main {
min-height: 50vh;
}
.container {
max-width: 1200px;
margin: 0 auto;
padding: 0 20px;
}Then add this to functions.php:
// Inline critical CSS
function digifusion_child_inline_critical_css() {
$critical_css_file = get_stylesheet_directory() . '/assets/css/critical.css';
if ( file_exists( $critical_css_file ) ) {
$critical_css = file_get_contents( $critical_css_file );
echo '<style id="critical-css">' . $critical_css . '</style>';
}
}
add_action( 'wp_head', 'digifusion_child_inline_critical_css', 1 );Resource Hints and Prefetching
// Add resource hints for better performance
function digifusion_child_resource_hints( $urls, $relation_type ) {
switch ( $relation_type ) {
case 'dns-prefetch':
$urls[] = '//fonts.googleapis.com';
$urls[] = '//fonts.gstatic.com';
break;
case 'preconnect':
$urls[] = array(
'href' => 'https://fonts.googleapis.com',
'crossorigin',
);
break;
case 'prefetch':
if ( is_front_page() ) {
$urls[] = get_permalink( get_option( 'page_for_posts' ) );
}
break;
}
return $urls;
}
add_filter( 'wp_resource_hints', 'digifusion_child_resource_hints', 10, 2 );Advanced Caching Functions
// Custom transient caching for expensive operations
function digifusion_child_get_cached_menu( $location ) {
$cache_key = 'digifusion_menu_' . $location;
$menu_html = get_transient( $cache_key );
if ( false === $menu_html ) {
ob_start();
wp_nav_menu( array(
'theme_location' => $location,
'container' => false,
'echo' => false
) );
$menu_html = ob_get_clean();
set_transient( $cache_key, $menu_html, 12 * HOUR_IN_SECONDS );
}
return $menu_html;
}
// Clear menu cache when menus are updated
function digifusion_child_clear_menu_cache() {
delete_transient( 'digifusion_menu_primary' );
delete_transient( 'digifusion_menu_footer' );
}
add_action( 'wp_update_nav_menu', 'digifusion_child_clear_menu_cache' );Performance Monitoring
Create assets/js/performance-monitor.js:
// Performance monitoring script
(function() {
'use strict';
// Monitor Core Web Vitals
function measurePerformance() {
if ('performance' in window && 'getEntriesByType' in performance) {
// Measure page load time
window.addEventListener('load', function() {
const navigation = performance.getEntriesByType('navigation')[0];
const loadTime = navigation.loadEventEnd - navigation.fetchStart;
console.log('Page Load Time:', loadTime + 'ms');
// Send to analytics if needed
if (window.gtag) {
gtag('event', 'timing_complete', {
name: 'load',
value: Math.round(loadTime)
});
}
});
// Measure First Contentful Paint
const observer = new PerformanceObserver(function(list) {
for (const entry of list.getEntries()) {
if (entry.name === 'first-contentful-paint') {
console.log('FCP:', entry.startTime + 'ms');
}
}
});
observer.observe({entryTypes: ['paint']});
}
}
// Initialize performance monitoring
if (document.readyState === 'loading') {
document.addEventListener('DOMContentLoaded', measurePerformance);
} else {
measurePerformance();
}
})();Add this to enqueue the performance monitor:
// Enqueue performance monitoring (only in development)
function digifusion_child_enqueue_performance_monitor() {
if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
wp_enqueue_script(
'digifusion-performance-monitor',
get_stylesheet_directory_uri() . '/assets/js/performance-monitor.js',
array(),
wp_get_theme()->get( 'Version' ),
true
);
}
}
add_action( 'wp_enqueue_scripts', 'digifusion_child_enqueue_performance_monitor' );