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When packaging a blank blueprint project in the versions mentioned, it adds the 'Slate' folder content to the final packaged product. I am not sure this is intended as the user does not need any of the assets for their project from the Slate folder.
The expected outcome would have the packaged product folder without the extra and uneeded content from the 'Slate' folder.
1) Make a blank project and add nothing at all
2) Package the project for Windows
3) Watch the debug for packaging add Slate content for Engine
4) Check inside the folder .../Engine/Content/Slate
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