Can solve with

\defineenumeration[remark][
  alternative=serried,
  width=fit,
  text={{\it Remark}},
  headstyle=\tf,
  indenting={first,medium},
  %headcommand=\groupedcommand{\hskip 1em}{},
]

Mikael Sundqvist via ntg-context <ntg-context@ntg.nl> 於 2021年12月31日 週五 上午4:55寫道：

Hi,

I have two questions:

1) What is the correct way to indent the first line of a (serried)
enumeration? In the example below, I can use headcommand, but then I
do not know what I should replace "1em" below to fit the medium
indenting.

2) I miss a numberstyle. What is the correct way to (in the example
below) get Remark in italic and the number upright?

/Mikael

\defineenumeration[remark][
  alternative=serried,
  width=fit,
  text=Remark,
  headstyle=italic,
  indenting={yes,medium},
  %headcommand=\groupedcommand{\hskip 1em}{},
]

\starttext

\samplefile{tufte}

\startremark
This line should be indented. The next line should not be indented. I
wonder how we can fix that.

This line is fine and is here for comparison.
\stopremark

\samplefile{tufte}

\stoptext
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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________