I noticed the same thing. If you have a flexible content field that has a repeater inside and you duplicate that flexible content field there is an issue with duplicating the fields inside the repeater. All looks well until you save the field group. Then you’ll notice that the everything duplicated beautifully…except the fields inside the repeater. If you look in the newly created flexible content field and open the repeater, you’ll find that there are no fields in it. If you open the repeater that is inside the original flexible content field, you’ll see 2 of each field.
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