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Please provide a capx and precise steps to reproduce the bug.
Not possible.
It crashed the game I was creating.
It happens when you have 2 projects open in the same window. If you drag a layout, from 1 project, into another layout, on a different project...from the Projects panel.
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Indeed, moving a layout from a project to another raises a check failure dialog.
Nevertheless clicking on ignore appeared to still copy the layout and allowing to continue working/saving.
I did select "Ignore", but it crashed anyway.