Switching from TCPDF to dompdf – due to image rendering / scaling / quality difficulties with TCPDF – I (unsurprisingly) stumbled upon some differences how dompdf handles the provided HTML. One of which is the way explicit page breaks can be accomplished. TCPDF expects you to use a special pagebreak attribute:

Whereas dompdf pays attention to the page-break-* CSS properties. A TCPDF-style replacement for an explicit page break might look like this: