Warning: Illegal string offset 'url' in vendor/tecnickcom/tcpdf/tcpdf.php on line 18807

#0 vendor/tecnickcom/tcpdf/tcpdf.php(18807): __error(2, 'Illegal string ...', '/var/www/vhosts...', 18807, Array)
#1 vendor/tecnickcom/tcpdf/tcpdf.php(18278): TCPDF->openHTMLTagHandler(Array, 56, 0)
#2 system/modules/core/modules/ModuleArticle.php(388): TCPDF->writeHTML('