add better check

Author: pfefferle

includes/functions.php

@@ -555,14 +555,19 @@ function webmentions_open( $post = null ) {
 	$open    = false;
 	if ( $post ) {
 		// Always consider the home mention link page to be open.
-		if ( get_option( 'webmention_home_mentions' ) === $post->ID ) {
+		if ( \get_option( 'webmention_home_mentions' ) === $post->ID ) {
 			$open = true;
-		} elseif ( ! post_type_supports( get_post_type( $post ), 'webmentions' ) ) {
+		} elseif ( ! \post_type_supports( \get_post_type( $post ), 'webmentions' ) ) {
 			// If the post type does not support Webmentions do not even check further.
 			$open = false;
 		} else {
-			// If the webmentions_disabled meta key exists then consider webmentions closed. Otherwise consider them open.
-			$open = ! ( metadata_exists( 'post', $post_id, 'webmentions_disabled' ) ); // Invert the result, as exists is closed and not exists is open.
+			$disabled = \get_post_meta( $post_id, 'webmentions_disabled', true );
+
+			if ( '1' === $disabled ) {
+				$open = false;
+			} else {
+				$open = true;
+			}
 		}
 	}