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Fatal error: Uncaught TypeError: mysqli_query(): Argument #1 ($mysql) must be of type mysqli, null given in /home/larkens/public_html/beheer/library.php:36 Stack trace: #0 /home/larkens/public_html/beheer/library.php(36): mysqli_query(NULL, 'select filename...') #1 /home/larkens/public_html/beheer/library.php(65): show_picture('po_schuilstal') #2 /home/larkens/public_html/projectenoverzicht.php(38): img_replace('Op deze pagina ...') #3 {main} thrown in /home/larkens/public_html/beheer/library.php on line 36