Missing Open Graph tags

How to fix

1. 1

   Via Yoast SEO (automatic)

   Yoast SEO automatically generates OG tags from the title and meta description. Customize image/title/description for each page in the Yoast "Social" tab.

2. 2

   Set the Open Graph image

   For each post/page: Yoast SEO → "Social" tab → upload a specific 1200×630px image. For the site in general: Yoast → Search Appearance → "Social" tab.

3. 3

   Manually in functions.php

   php

   add_action('wp_head', function() {
     if (is_singular()) {
       global $post;
       $img = get_the_post_thumbnail_url($post, 'large');
       echo '<meta property="og:title" content="' . esc_attr(get_the_title()) . '">';
       echo '<meta property="og:description" content="' . esc_attr(get_the_excerpt()) . '">';
       if ($img) echo '<meta property="og:image" content="' . esc_url($img) . '">';
       echo '<meta property="og:url" content="' . esc_url(get_permalink()) . '">';
       echo '<meta property="og:type" content="article">';
     }
   });