This was never a problem a before, but seems now to be after the update.
I make copper flood planes on borth sides of my PCB, usually with the exact same outline.
Previously it was possible to select each layer individually for rebuilt, but it was finicky. Now it does not work at all.
My suggestion is that if one for example select Top Layer, then it should only be able to select a copper layer on the top layer and vice versa for the bottom layer.
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