Is your feature request related to a problem? Please describe.
By default users name is readed from name field in identity response from custom OAuth provider. Some providers in name field stores username not a user full name and that results in all user having username as name in Rocket.Chat.

Describe the solution you'd like
In Custom OAuth provider configuration add field to specify from which field in identity response user full name should be mapped.
Describe alternatives you've considered
Alternative is custom script outside of Rocket.Chat that will periodically sync user name by REST API. This is prone to errors if REST API is changed and not maintainable on long run.
Is your feature request related to a problem? Please describe.

By default users name is readed from
namefield in identity response from custom OAuth provider. Some providers innamefield stores username not a user full name and that results in all user having username as name in Rocket.Chat.Describe the solution you'd like
In Custom OAuth provider configuration add field to specify from which field in identity response user full name should be mapped.
Describe alternatives you've considered
Alternative is custom script outside of Rocket.Chat that will periodically sync user name by REST API. This is prone to errors if REST API is changed and not maintainable on long run.