- Conditions were in the wrong order. We want to check for the existe…

…nce of `$args['capabilities']` before typing checking. If the first expression fails we skip the second, otherwise there'll be a PHP error.

lib/compat/wordpress-6.4/blocks.php

@@ -14,7 +14,7 @@
  */
 function gutenberg_add_custom_capabilities_to_wp_block( $args ) {
 	if ( is_array( $args ) ) {
-		if ( is_array( $args['capabilities'] ) || ! isset( $args['capabilities'] ) ) {
+		if ( ! isset( $args['capabilities'] ) || is_array( $args['capabilities'] ) ) {
 			$args['capabilities']['delete_posts'] = 'delete_posts';
 		}
 	}