Documentation Link

https://matplotlib.org/stable/gallery/user_interfaces/mplcvd.html

Problem

I copied the mplcvd example from @QuLogic's #20649 (thanks for the original implementation!), but that PR did not implement the UI for gtk4 (likely because it predates gtk4 support in Matplotlib).

Suggested improvement

Update the mplcvd example to support gtk4. This will require some knowledge of that tookit's API...