system.perspective.openPopup() draggable parameter

8.3.3

When I am using system.perspective.openPopup() to open a popup I don't see any difference when parameter draggable is True or False. My popop contains a powerchart where dragging is needed without moving the popup.
Where do I go wrong?

Does the popup fit on the screen? The only time the whole popup should be draggable is when it doesn't fit on the page so it doesn't get stuck

About half the size of the screen.

What do you expect when draggable is set to True or False?

It allows to user to move or not move the popup on the screen.

In our project we see that when the parameter draggable is set to False we stil can move the popup around the screen.