Ticket #51390: 51390.1.patch

src/wp-includes/theme.php

@@ -2517 +2517 @@
                                 unset( $post_formats['standard'] );
 
                                 $args[0] = array_intersect( $args[0], array_keys( $post_formats ) );
+                        } else {
+                                _doing_it_wrong( "add_theme_support( 'post-formats' )", __( 'You need to pass an array of types.' ), '5.6.0' );
+                                return false;
                         }
                         break;