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The auto-login feature requires several changes on the front end and back end of the service that is going to be integrated.
Prerequisites
A pre-shared secret key is used to verify that the login request is valid and coming from your (client’s) backend. Each service desk project has its own secret key. To obtain the key, open your project, and go to Project Settings > Chat Settings > Widget Functionality > Registration & Log In.
Here, enable the Auto - Login feature, and click the 
icon to generate a new then click Generate secret key:
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The pre-shared secret key should be stored on the backend.
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