diff --git a/includes/model/class-blog-user.php b/includes/model/class-blog-user.php
index 317eaab..062b616 100644
--- a/includes/model/class-blog-user.php
+++ b/includes/model/class-blog-user.php
@@ -204,7 +204,7 @@ class Blog_User extends User {
 	}
 
 	public function get_attachment() {
-		return null;
+		return array();
 	}
 
 	public function get_canonical_url() {
diff --git a/includes/model/class-user.php b/includes/model/class-user.php
index d07534b..f62772d 100644
--- a/includes/model/class-user.php
+++ b/includes/model/class-user.php
@@ -304,6 +304,10 @@ class User extends Actor {
 		return null;
 	}
 
+	public function get_tag() {
+		return array();
+	}
+
 	public function get_indexable() {
 		if ( \get_option( 'blog_public', 1 ) ) {
 			return true;