With the fill details option you can also decide to make a newly created detail (e.g. email) primary. However, if the detail already exists, but is not primary, it won't be touched. Even though this does make some kind of sense from an algorithmic point of view, the outcome ("email X is only to become primary if it doesn't already exist") is not what people would expect.
Therefore, if the 'make new detail primary' is active, even existing details should be made primary, if submitted.
bjendres
commented
5 years ago
With the fill details option you can also decide to make a newly created detail (e.g. email) primary. However, if the detail already exists, but is not primary, it won't be touched. Even though this does make some kind of sense from an algorithmic point of view, the outcome ("email X is only to become primary if it doesn't already exist") is not what people would expect.
Therefore, if the 'make new detail primary' is active, even existing details should be made primary, if submitted.