Intermesh
oauth client error
ErrorException Undefined array key "oauth2state"
callback url: https://groupoffice.wmservice.duckdns.org/groupoffice/go/modules/community/oauth2client/gauth.php/callback?state=xxxxxxxxxxxxxx&code=xxxxxxxxxxxxxx&scope=email%20profile%20https://mail.google.com/%20openid%20https://www.googleapis.com/auth/userinfo.profile%20https://www.googleapis.com/auth/userinfo.email&authuser=0&prompt=consent
I tried reproducing this against the last GO 6.8 version, but I can refresh my token without a problem.
The error you are getting, is that a session variable was lost. I cannot tell why that happens on your server, but as of the next version, a more helpful error message will be returned if this happens.
