To have awareness on interacting for the second time, the user is able to differentiate between edited and non edited items.
Here is a picture of the element :
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One design suggestion is to split the table into two tables - one for already-edited and one for non-edited. In this way you can give each table a title to describe its purpose.
Alternatively, keep everything in one table, and place the text "Edited" next to the items which have been edited.
Or perhaps use a tick icon to indicate edited? I personally tend to avoid icons where its meaning could be ambiguous or confusing, which is why it might be better to be explicit with text.