Snippets repository for WordPress developpers

// into functions.php
add_theme_support( 'body-open' );

// into header.php
<?php wp_body_open(); ?>

// into any page or template
<?php
if ( has_nav_menu( 'main' ) ) {
  wp_nav_menu(
    array(
      'container' => 'nav',
      'container_class'	=> 'main-menu',
      'items_wrap' => '<ul>%3$s</ul>',
      'menu_id'	=> '',
      'menu_class' => '',
      'theme_location' => 'main'
    )
  );
}
?>

// into functions.php
$logo_width  = 120;
$logo_height = 90;
// If the retina setting is active, double the recommended width and height.
if ( get_theme_mod( 'retina_logo', false ) ) {
  $logo_width  = floor( $logo_width * 2 );
  $logo_height = floor( $logo_height * 2 );
}
add_theme_support(
  'custom-logo',
  array(
    'height'      => $logo_height,
    'width'       => $logo_width,
    'flex-height' => true,
    'flex-width'  => true,
  )
);

// Use in theme files
<?php the_custom_logo();?>

// functions.php
add_filter( 'jpeg_quality', function( $arg ) {
  return 100;
});

// functions.php
add_image_size( 'sp_cover', 1980, 1200, true );
add_filter( 'image_size_names_choose', 'sp_custom_image_sizes' );
function sp_custom_image_sizes( $sizes ) {
  return array_merge( $sizes, array(
    'sp_cover' => __( 'Rosa cover' ),
  ) );
}

// functions.php
function clean_post_classes( $classes ) {
  if( ! is_array( $classes ) )
    return $classes;
    $allowed_classes = array(
      'hentry',
      'type-' . get_post_type(),
    );
    return array_intersect( $classes, $allowed_classes );
}
add_filter( 'post_class', 'clean_post_classes', 5 );

// functions.php
function clean_nav_menu_classes( $classes ) {
  if( ! is_array( $classes ) )
     return $classes;
  foreach( $classes as $i => $class ) {
    // Remove class with menu item id
    $id = strtok( $class, 'menu-item-' );
    if( 0 < intval( $id ) )
      unset( $classes[ $i ] );
    // Remove menu-item-type-*
    if( false !== strpos( $class, 'menu-item-type-' ) )
       unset( $classes[ $i ] );
    // Remove menu-item-object-*
    if( false !== strpos( $class, 'menu-item-object-' ) )
      unset( $classes[ $i ] );
    // Change page ancestor to menu ancestor
    if( 'current-page-ancestor' == $class ) {
      $classes[] = 'current-menu-ancestor';
      unset( $classes[ $i ] );
    }  
  }

  // Remove submenu class if depth is limited
  if( isset( $args->depth ) && 1 === $args->depth ) {
    $classes = array_diff( $classes, array( 'menu-item-has-children' ) );
  }
  return $classes;
}
add_filter( 'nav_menu_css_class', 'clean_nav_menu_classes', 5 );

// functions.php
function singular_body_class( $classes ) {
  if( is_singular() )
    $classes[] = 'singular';
  return $classes;
}
add_filter( 'body_class', 'singular_body_class' );

// function.php
// Alter dns-prefetch links
add_filter('wp_resource_hints', function (array $urls, string $relation): array {
    // If the relation is different than dns-prefetch, leave the URLs intact
    if ($relation !== 'dns-prefetch') {
        return $urls;
    }
    // Remove s.w.org entry
    $urls = array_filter($urls, function (string $url): bool {
        return strpos($url, 's.w.org') === false;
    });
    return array_merge($urls);
}, 10, 2);

// Remove infos about WordPress version
remove_action('wp_head', 'wp_generator');

// Remove emoji script and styles
remove_action('wp_head', 'print_emoji_detection_script', 7);
remove_action('wp_print_styles', 'print_emoji_styles');

// Remove REST-API link
remove_action('wp_head', 'rest_output_link_wp_head');

// Disable XML-RPC
add_filter('xmlrpc_enabled', function (): bool {
    return false;
});

// Remove XML-RPC link
remove_action('wp_head', 'rsd_link');

// Remove Windows Live Writer manifest
remove_action('wp_head', 'wlwmanifest_link');

// Disable RSS feeds by redirecting their URLs to homepage
foreach (['do_feed_rss2', 'do_feed_rss2_comments'] as $feedAction) {
    add_action($feedAction, function (): void {
        // Redirect permanently to homepage
        wp_redirect(home_url(), 301);
        exit;
    }, 1);
}

// Remove the feed links
remove_action('wp_head', 'feed_links', 2);

// Remove unnecessary attributes from style tags
add_filter('style_loader_tag', function (string $tag, string $handle): string {
  // Remove ID attribute
  $tag = str_replace("id='${handle}-css'", '', $tag);
  // Change ' to " in attributes:
  $tag = str_replace('\'', '"', $tag);
  // Remove trailing slash
  $tag = str_replace(' />', '>', $tag);
  // Remove double spaces
  return str_replace('  ', '', $tag);
}, 10, 2);

// functions.php
add_theme_support( 'responsive-embeds' );