Thanks for the update. So when you tile or stretch the cropped image it reverts to the original. Something I hadn't even tried.
Not sure why that would have changed between 11.3 and 11.3.1 but thinking about it, there may be an easy workaround.
When we crop an image with Preview or Photos, the previous versions are kept so we can Revert to Original.
Preview, File > Revert To > Previous Save or Browse All Versions
Photos, Image > Revert to Original
To stop that from happening, we can Export or Save As a new copy that has no History.
Preview, Option-File > Save As
Preview, File > Export
Photos, File > Export > Export 1 Photo…
Then use that new copy with no History so there is no previous version possible for the Desktop.
Let me know how that works for you.
ivan