[NTG-context] hard clipping in ConTeXt?

Dear list, I have the following sample: \setuplayout[page] \starttext \clip[hoffset=5mm, voffset=5mm, width=15mm, height=15mm] {\externalfigure[xml-mkiv.pdf]} \stopnotmode \stoptext Using PDF.js (from current Firefox), xpdf, Evince, mupdf-gl, the viewer is able to find "dealing", altough it cannot be displayed. Okular and Sumatra (with Wine in Linux) are not able to find "dealing". Is there any way to have a hard clipping in ConTeXt? I mean, that only the contents of the clipped section is added to the resulting PDF document? Many thanks for your help, Pablo