[NTG-context] \placefigure[margin] but in left margin?

Dear list, I want to have the effect I get with \placefigure[margin] but I want it _always_ in the left margin instead of the right margin where it ends up by default. I have tried several other keys but with leftmargin, inleft the figure is not put in the top of the page, "independent of the text". Can I fix this with some setup? Small test file: \starttext \input tufte \placefigure[leftmargin][none]{With the key leftmargin}{\externalfigure[cow][width=1cm]} \input tufte \placefigure[inleft][none]{With the key inleft}{\externalfigure[cow][width=1cm]} \input tufte \placefigure[margin][none]{With the key margin}{\externalfigure[cow][width=1cm]} \input tufte % This is the way I want it, but I want it in the left margin instead \stoptext