\setupbodyfont[dejavu]

\useMPlibrary
  [dum]

\setupfloat
  [figure]
  [default=top]


\ctxlua{structures.lists.autoreorder = true}

\starttext

\input knuth

\startplacefigure
  \externalfigure [dummy]
\stopplacefigure

\startplacefigure
  \externalfigure [dummy] [width=10cm, height=16cm]
\stopplacefigure

\startplacefigure
  \externalfigure [dummy]
\stopplacefigure

\stoptext


