In the Facebook's Graph API, once we have initially authenticated the user, we can interact directly with the API (from the server) to obtain a long-lived page access token. This long-lived page access token never expires. (https://developers.facebook.com/docs/facebook-login/access-tokens/)
In reading LinkedIn's documentation, it appears that it is impossible to obtain an access token with an indefinite (non-expiring) access token. It seems that they expire every 60 days. However, these access tokens can be refreshed before the 60 days is up.
What isn't entirely clear from the documentation is whether or not the access token renewal can be performed on the server alone without the client's interaction. The language of the documentation suggests that the interaction of the client (browser) is required, but nothing is explicitly stated.
So, my question is, is it possible to renew a LinkedIn access token using the server alone, without the interaction of the client (browser)?
Relevant LinkedIn reference material: https://developer.linkedin.com/documents/handling-errors-invalid-tokens