[NTG-context] Placing text in the margin of a header or the top right corner of a page

Dear All, I am trying to place a framed text in the top right corner of each page of a screen document and it looks like (cont-eni) some invocation of \setupheadertexts might do the job. Unfortunately, I have only been able to place my text in the margin of the body of the page, using \margintext. Ideally, I would like to have the framed text box flush with the top and right edge of a page, but any approximate solution or a pointer to some document to read (that could educate me) will be much appreciated. Thanks, Matthias