Use the OAuth authentication standard to connect to LinkedIn.
OAuth requires the authenticating user to interact with LinkedIn using the browser. The add-in facilitates this in various ways as described below.
See Embedded Credentials
to connect with the add-in's embedded credentials and skip creating a custom OAuth app.
Instead of connecting with the add-in's embedded credentials, you can register an app to obtain the OAuthClientId and OAuthClientSecret.
When to Create a Custom OAuth App
Creating a custom OAuth app is optional as the add-in is already registered with LinkedIn and you can connect with its embedded credentials.
You might want to create a custom OAuth app to change the information displayed when users log into the LinkedIn OAuth endpoint to grant permissions to the add-in.
Creating a Custom OAuth App
See Creating a Custom OAuth App for a procedure.