The Captions tab in Gopher Options is used to change the name of certain fields in Gopher. The Profile tab, Position tab, Tracking tab and the Target List contain user defined fields.
Captions are database specific. The database that the user ID of GO4 is pointed to on the User tab is the database that will be updated when changes are made to Captions.

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User Defined Fields on Profile tab
User Defined Fields on Position tab
User Defined Fields on Tracking tab