Plot rendering error: 'NoneType' object has no attribute 'bbox'; metadata = {'Entries': 20378, 'Name': 'OccupancyDist-2', 'Overflow': 2107.0, 'Type': 'Histo1d', 'Underflow': 131115.0, 'x': {'AxisTitle': 'Occupancy', 'Bins': 49, 'High': 49.5, 'Low': 0.5}, 'y': {'AxisTitle': 'Number of Pixels'}, 'z': {'AxisTitle': 'z'}}