How to hang glass window hanger at upvc window?

[Lastyearsmodel]

I'm stumped - I have a lovely glass hanger/panel thing (quite small, about 20cm) I want to hang at a window but all of ours are upvc framed - any ideas how I can do it? My experience of suction hooks has not been good and I don't want to risk smashing it.

Screw it into the ceiling of the window, iyswim?

Not thought of that, thanks Dawny. The way our windows are it would spin, though. Still racking my brains to think of a way.

Hang it off the curtain rail?

Small plastic stick-on hook (the sort you hang tea towels on).