Describe the bug in 1-2 short sentences

If possible, please provide a minimum self-contained example.

Paste the output produced by the code provided above, e.g.
console output, images/videos produced by the code, any relevant screenshots/screencasts, etc.

Describe (or provide a visual example of) the expected outcome from the code snippet.

• What are the conditions under which this bug happens? input parameters, edge cases, etc?
• Has this worked in earlier versions?
• Do you know why this bug is happening?
• Do you maybe even know a fix?

Windows, OS/X, Arch, Debian, Ubuntu, etc.

From Python prompt: import matplotlib; print(matplotlib.__version__)

From Python prompt: import matplotlib; print(matplotlib.get_backend())

In console: python --version

In console: jupyter notebook --version or jupyter lab --version

How did you install matplotlib?