[NTG-context] How to change the color of numbers just before the footnote text?

Now I have to change the color of numbers just before the footnote text so that it can match the color of text area. I try to do it like this: \def\myfootnotecolor#1{% \startcolor[red]#1\stopcolor} \setupfootnotes [numbercommand={\myfootnotecolor}] or \setupfootnotes [foregroundcolor=red] either method has no effect.