Fatal error: Uncaught Error: Call to undefined function register_rest_field() in /wp-content/plugins/wp-smushit/core/modules/class-wp-smush-rest.php:40 Stack trace: #0 /wp-includes/plugin.php(524): WP_Smush_Rest->register_smush_meta(Object(WP_REST_Server)) #1 /wp-includes/rest-api.php(294): do_action('rest_api_init', Object(WP_REST_Server)) #2 /wp-includes/rest-api.php(144): rest_get_server() #3 /wp-includes/plugin.php(600): rest_api_loaded(Object(WP)) #4 /wp-includes/class-wp.php(388): do_action_ref_array('parse_request', Array) #5 /wp-includes/class-wp.php(727): WP->parse_request('') #6 /wp-includes/functions.php(1015): WP->main('') #7 /wp-blog-header.php(16): wp() #8 /index.php(17): require('/wp-blog-header...') #9 {main} thrown in /wp-content/plugins/wp-smushit/core/modules/class-wp-smush-rest.php on line 40