The following required properties are missing: fb:app_id (Meta Sharing Debugger)

If the Meta Sharing Debugger displays the message "The following required properties are missing: fb:app_id," there's nothing to fix: your code is fine, and the shared content displays correctly. The fb:app_id tag isn't required, and Facebook no longer uses it.

What this warning means

Meta's Sharing Debugger previews how a URL looks when shared on Facebook and flags code issues that could affect the result. One of the things it checks is whether the fb:app_id meta tag is present: when it can't find the tag, it displays the message "The following required properties are missing: fb:app_id."

What fb:app_id was for (and why it no longer works)

The fb:app_id tag was part of Domain Insights, Facebook's analytics product: when someone clicked "Like" on your content using the button embedded on the page, the app_id value indicated which Facebook page could view those statistics. Facebook began shutting down Domain Insights in 2016, and the analytics features provided by the tag came to require a Facebook Pixel instead.

Earlier versions of the message also explained that app_id enabled interactions with "stories" (Open Graph Stories) to be attributed correctly. Facebook ended support for Open Graph Stories in 2018. With both features discontinued, the fb:app_id tag fell out of use across the entire Facebook ecosystem.

Why the warning appears on your site

The warning appears because the Debugger still looks for the tag, even though Facebook no longer uses it. It's common to see this on sites with Yoast SEO: the plugin had a field for entering an fb:app_id value and generated the tag on every page, but Yoast removed this feature in version 15.5. The other Open Graph tags (og:title, og:description, and others) are still generated as usual; only fb:app_id was removed.

How to remove the warning (if you still want to)

We recommend doing nothing: the warning doesn't indicate a real problem. If you'd still rather not see it, the only solution is to add the fb:app_id tag back yourself, because Yoast SEO no longer generates it.

1. Edit your child theme's functions.php file, or include the code in a custom plugin. If you modify the theme directly, a theme update could overwrite the change, so using a child theme is a good idea.

2. Add this function:

function mi_fb_app_id() {
  $app_id = '966242223397117';
  echo '<meta property="fb:app_id" content="' . $app_id . '" />';
}
add_action( 'wp_head', 'mi_fb_app_id' );

The value 966242223397117 is Facebook's default "APP ID": any site can use it, and it makes the debugger error disappear. If you have your own Facebook app, replace it with your app's ID.

Keep reading

If you'd like to learn more about controlling the preview of your links on social media, see Open Graph and social meta tags: how to control your link previews.