pyvista: Python does not respond after closing a plot

Hi, when I plot something with PyVista plotter using IPython, it shows the figure correctly and I can interact with it (like rotating), but when I close the plot Python does not respond anymore, the plot is completely frozen and I have to manually do a “force quit” of Python.

However, I do not encounter this problem when I run the script directly from the command line using the python -m command but I get an error message instead. Please find more details below.

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To Reproduce

After cloning the PyVista repository from GitHub, running python -m pip install -e . and upgrading PyVista to the latest version (0.25.3 at this moment), I run an example which shows how to create a PolyData object (https://docs.pyvista.org/examples/00-load/create-poly.html) through IPython :

import numpy as np
import pyvista as pv

# mesh points
vertices = np.array([[0, 0, 0],
                     [1, 0, 0],
                     [1, 1, 0],
                     [0, 1, 0],
                     [0.5, 0.5, -1]])

# mesh faces
faces = np.hstack([[4, 0, 1, 2, 3],  # square
                   [3, 0, 1, 4],     # triangle
                   [3, 1, 2, 4]])    # triangle

surf = pv.PolyData(vertices, faces)

# plot each face with a different color
surf.plot(scalars=np.arange(3), cpos=[-1, 1, 0.5])

You should observe that Python does not respond anymore when you try to close the figure.

As mentioned above, I do not encounter the problem when I run directly the script with the python -m command, but the command line displays

/usr/local/opt/python/bin/python3.7: Error while finding module specification for 'create-poly.py' (ModuleNotFoundError: __path__ attribute not found on 'create-poly' while trying to find 'create-poly.py')

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System Information:

                OS : Darwin
            CPU(s) : 8
           Machine : x86_64
      Architecture : 64bit
       Environment : IPython
        GPU Vendor : ATI Technologies Inc.
      GPU Renderer : AMD Radeon Pro 580 OpenGL Engine
       GPU Version : 4.1 ATI-3.9.15

  Python 3.7.7 (default, Mar 30 2020, 10:31:28)  [Clang 11.0.3
  (clang-1103.0.32.29)]

           pyvista : 0.25.3
               vtk : 9.0.0
             numpy : 1.18.1
           imageio : 2.8.0
           appdirs : 1.4.3
            scooby : 0.5.5
            meshio : 4.0.15
        matplotlib : 3.1.2
           IPython : 7.11.1
             scipy : 1.4.1

Hope this can be fixed as soon as possible !