Ticket #16707: 16707.3.diff

src/wp-includes/class-wp-theme.php

@@ -673 +673 @@
                                         /* translators: used between list items, there is a space after the comma */
                                         $comma = __( ', ' );
                                 }
-                                $value = implode( $comma, $value );
+                                if( is_array( $value ) ){
+                                        $value = implode( $comma, $value );
+                                }
                                 break;
                         case 'ThemeURI' :
                         case 'AuthorURI' :