Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "_return_false" not found or invalid function name in /www/htdocs/w014e411/q-bar.de/wp-includes/class-wp-hook.php:308
Stack trace:
#0 /www/htdocs/w014e411/q-bar.de/wp-includes/plugin.php(205): WP_Hook->apply_filters(true, Array)
#1 /www/htdocs/w014e411/q-bar.de/wp-includes/rest-api/class-wp-rest-server.php(302): apply_filters('rest_jsonp_enab...', true)
#2 /www/htdocs/w014e411/q-bar.de/wp-includes/rest-api.php(410): WP_REST_Server->serve_request('/oembed/1.0/emb...')
#3 /www/htdocs/w014e411/q-bar.de/wp-includes/class-wp-hook.php(308): rest_api_loaded(Object(WP))
#4 /www/htdocs/w014e411/q-bar.de/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters('', Array)
#5 /www/htdocs/w014e411/q-bar.de/wp-includes/plugin.php(565): WP_Hook->do_action(Array)
#6 /www/htdocs/w014e411/q-bar.de/wp-includes/class-wp.php(399): do_action_ref_array('parse_request', Array)
#7 /www/htdocs/w014e411/q-bar.de/wp-includes/class-wp.php(780): WP->parse_request('')
#8 /www/htdocs/w014e411/q-bar.de/wp-includes/functions.php(1334): WP->main('')
#9 /www/htdocs/w014e411/q-bar.de/wp-blog-header.php(16): wp()
#10 /www/htdocs/w014e411/q-bar.de/index.php(17): require('/www/htdocs/w01...')
#11 {main}
thrown in /www/htdocs/w014e411/q-bar.de/wp-includes/class-wp-hook.php on line 308