PR Summary

As the title suggests. The script below should enter full-screen and keypress "f" should toggle back and forth.

import matplotlib.pyplot as plt

fig = plt.figure()
fig.canvas.manager.full_screen_toggle() # toggle fullscreen mode
plt.show()

PR Checklist

Tests and Styling

• [N/A] Has pytest style unit tests (and pytest passes).
• [N/A] Is Flake 8 compliant (install flake8-docstrings and run flake8 --docstring-convention=all).

Documentation

• [N/A] New features are documented, with examples if plot related.
• [N/A] New features have an entry in doc/users/next_whats_new/ (follow instructions in README.rst there).
• [N/A] API changes documented in doc/api/next_api_changes/ (follow instructions in README.rst there).
• [N/A] Documentation is sphinx and numpydoc compliant (the docs should build without error).