GIMP script for cleaning pictures. It takes a background from a rectangular selection border and interpolates the selection contents based on this border.
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It is slow and doesn't support undo, so use at your own risk.
This script was built based on one of the features of my other project - the Unpager - https://github.com/akalenuk/unpager The Unpager can do darning not only for rectangular forms, but for any quadrilateral.
There is also an explanation of how it works on wordsandbuttons.online: https://wordsandbuttons.online/image_darning.html