Wouter, yes indeed typo. Now the warning is gone.
Dokken, the command “conda install -c conda-forge fenics-dolfinx mpich pyvista” is indeed what I used.
I prefer to continue with PyCharm, otherwise I will have two different development environments.
Apparently creating simple meshes has now changed to:
dolfinx.mesh.create_cube
dolfinx.mesh.create_rectangle
For other geometries I need to use gmsh as explained here:
Generating a (Rectangle-Circle)-Mesh in dolfinx - mesh - FEniCS Project