I am aware we have the function Duplicates() at our disposal. Nevertheless, this template makes use of what I call a Group Index.
The logic can be applied in various ways. For demonstration purposes I assumed it was easy to only set the buttons active that are on a row with a duplicate.
A duplicate is a row that is counted more than once, thus contains a number higher than 1 (2 → n)
A is created by filtering on the row itself while asking for the relative position in the table.
→ Click the button and you see it happen.
My blog about it:
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