Fatal error: Uncaught TypeError: call_user_func(): Argument #1 ($callback) must be a valid callback, non-static method youtube::render() cannot be called statically in /var/www/gruebisbalm/common/lib/embed.inc.php:61 Stack trace: #0 /var/www/gruebisbalm/common/lib/embed.inc.php(99): embed::choose() #1 [internal function]: embed::render() #2 /var/www/gruebisbalm/common/lib/embed.inc.php(32): preg_replace_callback() #3 /var/www/gruebisbalm/common/view.php(321): embed::parse() #4 /var/www/gruebisbalm/common/lib/embed.inc.php(61): content::render() #5 /var/www/gruebisbalm/common/lib/embed.inc.php(99): embed::choose() #6 [internal function]: embed::render() #7 /var/www/gruebisbalm/common/lib/embed.inc.php(32): preg_replace_callback() #8 /var/www/gruebisbalm/common/view.php(191): embed::parse() #9 /var/www/gruebisbalm/zugvogel/web/index.php(2): require_once('...') #10 {main} thrown in /var/www/gruebisbalm/common/lib/embed.inc.php on line 61