Excessive white space / margins with some plots.

[asteppke]

With the current ipympl 0.9.6 (and probably earlier versions) I am observing excessive white space around axes in some cases when using the %matplotlib ipympl mode but not in the %matplotlib inline mode.

A small example to reproduce:

%matplotlib ipympl
from matplotlib import pyplot as plt

fig, ax = plt.subplots(figsize=(5, 3), constrained_layout=True)
ax.imshow([[1,2,3],[4,5,6],[7,8,9]])
ax.set_aspect(0.1)

This yields:

And the same example in inline mode:

%matplotlib inline
from matplotlib import pyplot as plt

fig, ax = plt.subplots(figsize=(5, 3), constrained_layout=True)
ax.imshow([[1,2,3],[4,5,6],[7,8,9]])
ax.set_aspect(0.1)

Especially larger figures then became unmanageable in the ipympl backend. Setting constrained_layout or using plt.tight_layout() does not seem to influence the margins. Can this behavior be influenced?