GraphicsScene.mouseMoveEvent duplicates events

[TilmanK]

The current implementation of GraphicsScene.mouseMoveEvent calls the base class implementation twice, when QMouseEvent.buttons() is something else than Qt.MouseButton.NoButton. The duplicate call happens here:

pyqtgraph/pyqtgraph/GraphicsScene/GraphicsScene.py

Line 182 in 88c3127

super().mouseMoveEvent(ev)

I don’t see any reason at this point to call the base class handler again. In general, I think the event's should be duplicated and handled twice.