Can't plot 3D field in browser

[Anders Logg (Chalmers)]

The following code just gives me a blue box:

from fenics import *
mesh = UnitCubeMesh(8, 8, 8)
V = VectorFunctionSpace(mesh, 'P', 1)
v = project(Expression(('sin(x[0])', '-x[2]', 'x[3]'), degree=1), V)
import matplotlib
matplotlib.use('webagg')
import matplotlib.pyplot as plt
parameters['plotting_backend'] = 'matplotlib'
plot(v)
plt.show()

(Plotting in Browser from Docker container.)

[Prof Garth Wells]

You've picked Matplotlib, via which we don't support fir 3D plotting. (And I expect we never will - Matplotlib is awful for 3D).