On 2013–05–04 Zenlima wrote:

> I want to display the lowest heading in the outer margin. But as soon
> the simple text becomes a heading, a strange extra line appears on top
> of the margin. 
> 
> In my minimum example below the first paragraph shows how it should look
> like in the pdf-file; the second paragraph is with a heading in the
> margin. 
> 
> Can anyone tell me, 
> 
> 	a) how to get rid of the unwanted extra vertical space? 

You can use a custom headalternative setup:

\definesection [section-8]

\definehead
  [myheader] []
  [alternative=myheader,
   section=section-8]

\defineheadalternative
  [myheader]
  [alternative=horizontal,
   renderingsetup=setup:myheader]

\startsetups [setup:myheader]
  \inouter{\headtextcontent}
\stopsetups

\starttext
  \inouter{Hasselt makes headlines}
  \input tufte

  \myheader{Hasselt makes headlines}
  \input tufte
\stoptext

> 	b) Why is the line-break in the margin of the second paragraph
> 	different than above?

The margin box itself is positioned correctly, but I have no clue
where the empty line comes from. You can visualise the box with:

  \setupmarginframed [inouter] [frame=on]


Marco