Have you thought about adding the following line? What do you think about it?

h1,h2,h3,h4,h5,h6 { page-break-after:avoid; }

I could add it in the next version of the framework, something like h1,h2,h3,h4,h5,h6 { page-break-after:avoid; page-break-inside: avoid; }

Thanks for the suggestion