Is there any extension or standard option to view/edit attributed relationship records attributes using standard ArcMap attribute editor dialog? Same to question about identify dialog :)
I'm not sure if you are talking about the related records or the rows in the actual relationship class.
If it's the related records, the attribute editor provides some basic editing abilities:
And you can edit the field values of the related table:
Not sure if this is exactly what you're looking for, but I'll give it a shot. You can get to the related records with the Related Tables button in the attribute table (once you have a feature selected), which is editable.
In the Identify box you can see related records by using the + option under your main layer, but I don't believe it's editable.
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