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OpenId server: OpenId authentication server url. This is the URL translate5 redirects users for authentication at the OpenId connect server (Google configuration example: https://accounts.google.com)
OpenId issuer: OpenId issuer url. In many cases this url is identical with the OPenId server url.
OpenId user name: OpenId authentication server username (Google configuration example: "Client ID" see image3)
(the user name that allows the openId client application to connect to the API of the openId server; do NOT mix this up with the username of the user, that wants to authenticate!)
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