% \enabletrackers[graphics.floats]

\starttext

test
\dorecurse{20}{
    \ifodd\recurselevel\relax
        \placefigure[page,none]       {with    header \recurselevel}{}
    \else
        \placefigure[page,header,high]{without header \recurselevel}{}
    \fi
}
test \page test

\stoptext
