Related Posts

Jetpack’s Related Posts will automatically work with your site’s Posts, but you can also use it with other Custom Post Types you might have, like Events, a Portfolio, or even Products. In order to get Related Posts to index and display on your Custom Post Types, you will need to add this function and filter:

function allow_my_post_types($allowed_post_types) {
    $allowed_post_types[] = 'your-post-type';
    return $allowed_post_types;
}
add_filter( 'rest_api_allowed_post_types', 'allow_my_post_types' );

Please note you will need to edit the code above and replace your-post-type with your Custom Post Type. We also do advise that you Reindex your site so that Jetpack will know of the new changes. You can Reindex your site by clicking Jetpack on your site’s Dashboard, and scrolling down and clicking the “Debug” link at the bottom of the page. From there you will have a “Reindex Posts” available. If you are not seeing the Related Posts show up right away with your Custom Post Types, try clearing your browser and site’s cache.

Source: Using JetPack Related Posts for Custom Post Types

Other Helpful Documentation on Jetpack

Publicize

Jetpack’s Publicize module works quite well with Custom Post Types, you just have to enable it in your theme or in the functions.php : add_action(‘init’, ‘my_custom_init’); function my_custom_init() { add_post_type_support( ‘your-custom-post-type-name’, ‘publicize’ ); } You can also access it automatically once Jetpack is enabled in the Advanced Options tab under Edit Pods for your Custom Post Type, under Supports. …

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