zahar

Here, try to `/place structure my_namespace:test_street` on flat surface vs sloped.
you can even see mid way when it stops working, both upwards and downwards (no workaround for downwards except code change)

I don't see any attach button. Moreover the screenshots attachments disappeared as well.
I can send via email if its an option.

As a workaround (im working with fabric) i created mixin that simply expands the structure box in Y direction, so that the jigsaw block will be included inside the structure allowing the lamp to generate:

@Mixin(targets = "net.minecraft.structure.pool.StructurePoolBasedGenerator$StructurePoolGenerator")
public class StructurePoolGeneratorMixin {
    @ModifyVariable(method = "generatePiece", at = @At("STORE"), ordinal = 0)
    private BlockBox onGeneratePiece(BlockBox box) {
        return box.expand(0,10,0);
    }
}