Dear Support Team,
Getting duplicate slice measures while reorder grid header rows by drag and drop and then changing layout options in grid.
1.Set Flat View
2.Reorder slice rows by drag and drop grid headers
3.Set Compact View
4.Open Fields , then you can find measures getting added in rows also
Please find the fiddle link https://jsfiddle.net/ravimarch7/jLgo26cr/6/
Thank you for providing a JSFiddle example for illustration.
It helped us a lot to understand the problem better.
Our team will provide the fix to this issue in the minor release version with the ETA 27th of August.
You are welcome to contact us in case of questions.