Is there a way in MKII to ensure that there is never a page break between a
heading and the following text?

\setuphead[after={\page[no]}] does not seem to work without entering
vertical mode before \page. But, so far, I have not found a way to enter
vertical mode in after={…} that does not add interlinespace and thus place
the text too far from the heading.

Any suggestion or alternatives?

Alan