On Thu, 5 Sep 2019, Otared Kavian wrote:

> Hi Wolfgang,
>
> Thanks for your answer. I tried Hans' suggestion to use \textbackground instead of background: indeed it solves the problem of incorrect page breaks, but it seems that \setuptextbackground « leftframe=on » is not honoured, that is one cannot say for instance:
>
> 	\setuptextbackground[frame=off,leftframe=on]
>
> while using \background this would be possible.

See

https://adityam.github.io/context-blog/post/frame-with-solid-left-line-redux/

Aditya