title: After conda update, python kernel crashes when matplotlib is used
body: <p>I have create this simple env with <code>conda</code>:</p>
  <pre><code>conda create -n test python=3.8.5 pandas scipy numpy matplotlib seaborn jupyterlab
  </code></pre>
  <p>The following code in <code>jupyter lab</code> crashes the kernel :</p>
  <pre><code>import matplotlib.pyplot as plt
  
  plt.subplot()
  </code></pre>
  <p>I don't face the problem on <code>Linux</code>. The problem is when I try on <code>Windows 10</code>.</p>
  <p>There are no errors on the <code>jupyter lab</code> console (where I started the server), and I have no idea where to investigate.</p>