Depth mapping not working on jupyterlab3

Describe the bug, what’s wrong, and what you expected.

I have tried running the following example and I get the following error. While this example does not include the off_screen = True parameter I included it within show() but still get an error

Steps to reproduce the bug.

 import pyvista as pv
from pyvista import examples

# Load an interesting example of geometry
mesh = examples.load_random_hills()

# Establish geometry within a pv.Plotter()
p = pv.Plotter()
p.add_mesh(mesh, color=True)
p.store_image = True  # permit image caching after plotter is closed
p.show()

zval = p.get_image_depth() 

System Information

--------------------------------------------------------------------------`
AttributeError                            Traceback (most recent call last)
Input In [13], in <cell line: 1>()
----> 1 zval = p.get_image_depth()

File C:\Python\Miniconda\envs\test_3d\lib\site-packages\pyvista\plotting\plotting.py:3488, in BasePlotter.get_image_depth(self, fill_value, reset_camera_clipping_range)
   3485         zval[self._image_depth_null] = fill_value
   3486     return zval
-> 3488 self._check_rendered()
   3489 self._check_has_ren_win()
   3491 # Ensure points in view are within clipping range of renderer?

File C:\Python\Miniconda\envs\test_3d\lib\site-packages\pyvista\plotting\plotting.py:1241, in BasePlotter._check_rendered(self)
   1239 """Check if the render window has been shown and raise an exception if not."""
   1240 if not self._rendered:
-> 1241     raise AttributeError(
   1242         '\nThis plotter has not yet been set up and rendered '
   1243         'with ``show()``.\n'
   1244         'Consider setting ``off_screen=True`` 
   1245         'for off screen rendering.\n'
   1246     )

AttributeError: 
This plotter has not yet been set up and rendered with ``show()`
Consider setting ``off_screen=True`` for off screen rendering. '

Screenshots

No response

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[mllobera]

Great thanks!! I tried this and something weird happened. If I run it without the off_screen parameter I get the popup window and when I quit it, I get z-values as expected. However, when I try with off_screen = True all I get is nan.

[akaszynski]

Can you try with off_screen=True set on the Plotter?