Hmm, you’re right. My apologies; this appears to be a minor bug in Panda3D 1.1.0. But there’s a simple workaround: simply pass in the GSG (the graphics context) from the previous window, like this:
base.openMainWindow(props = props, gsg = base.win.getGsg())This is probably a good idea to do anyway, since it preserves all of the existing graphics context; without it, Panda would have to re-load all of the textures and so forth.
David