Adds a button to resize the viewed submission to fit within the dimension of your screen.
The button can be found below the submission image, clicking it twice will return the image to its original size.

This version is meant for the Furaffinity classic layout for the new beta layout use this: https://openuserjs.org/scripts/Artex/FA_Beta_-_Fit_to_Screen

As of 1.4 behavior is considerably more consistent and reliable between chrome and firefox.