Bug? kcFinder issue with Google Chrome (Mac)

I've added an image using the kcFinder button when editing an article and have successfully added an image.

I can then save the page but if I try to add another image the kcFinder browser hangs and the page goes unresponsive, requiring it to be killed.

This is in Google Chrome version 19.0.1084.46 on Mac - Safari etc is fine.