title: Why getContext() returns null on Chrome on Ubuntu
body: <p>Why getContext() returns null when called on existing canvas Element,
  but works fine when createElement('canvas').getContext()?</p>
  
  <p>Chrome 72.0.3626.121 on Ubuntu 18.04</p>
  
  <p>see chrome console:
  <a href="https://i.stack.imgur.com/HJTnl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HJTnl.png" alt="enter image description here"></a></p>