Comment 3 for bug 1076136

It's very unclear what you're asking here. It sounds like you're expecting openMainWindow() to reset the scene graphs, which is certainly not what it is supposed to do. If you wish to remove all objects, you must set up a new scene graph, not open a new window.

If you believe this is a bug, please attach a concise test case that we can run that reproduces the issue in question, and I will change the bug status back.