I have to use this hack to make section titles appear when I use section blocks (Hans, could you have a look at this bug of your s-pre-60.mkiv module when you have time please?):


\usemodule[pre-60]
\setupinteraction[state=start]

\starttext
   \startfrontmatter
      \StartSteps % <-- Hack
      \StopSteps % <-- Hack
      \startsection[title=My frontmatter section] % <-- Title displayed (the hack is not needed for this first section block, but I also use it here for symmetry with the next section blocks)
         \StartSteps
         \startitemize
            \item my item\FlushStep
            \item my item\FlushStep
            \item my item\FlushStep
         \stopitemize
         \StopSteps
      \stopsection
   \stopfrontmatter

   \startbodymatter