Warning: Cannot modify header information - headers already sent by (output started at /mnt/web014/c0/59/52182859/htdocs/index.php:1) in /mnt/web014/c0/59/52182859/htdocs/vendor/tecnickcom/tcpdf/tcpdf.php on line 7721

Fatal error: Uncaught Exception: TCPDF ERROR: Some data has already been output to browser, can't send PDF file in /mnt/web014/c0/59/52182859/htdocs/vendor/tecnickcom/tcpdf/tcpdf.php:3007
Stack trace:
#0 /mnt/web014/c0/59/52182859/htdocs/vendor/tecnickcom/tcpdf/tcpdf.php(7723): TCPDF->Error('Some data has a...')
#1 /mnt/web014/c0/59/52182859/htdocs/vendor/spipu/html2pdf/src/Html2Pdf.php(575): TCPDF->Output('zaehler_ablesen...', 'D')
#2 /mnt/web014/c0/59/52182859/htdocs/Components/Manual/Context.php(79): Spipu\Html2Pdf\Html2Pdf->output('zaehler_ablesen...', 'D')
#3 /mnt/web014/c0/59/52182859/htdocs/Components/Manual/Context.php(37): Bueroinform\Components\Manual\Context::getDisplayLines(Object(Bueroinform\Utils\ManualFactory), 6)
#4 /mnt/web014/c0/59/52182859/htdocs/index.php(234): Bueroinform\Components\Manual\Context::get()
#5 {main}
  thrown in /mnt/web014/c0/59/52182859/htdocs/vendor/tecnickcom/tcpdf/tcpdf.php on line 3007