My team has been using GitLab’s implicit grant flow to authenticate our users for our CMS (Netlify CMS) by redirecting our users to:
https://gitlab.com/oauth/authorize?client_id=<client_id>&redirect_uri=http://cms.29k.org&response_type=token&scope=api&state={"auth_type":"implicit","nonce":<nonce>}
which has been working fine until recently. Now, upon being redirected to the URL above, the user is met with the following error message:
An error has occurred: The authorization server encountered an unexpected condition which prevented it from fulfilling the request.
In addition, a second request is dispatched to GET https://gitlab.com/oauth/undefined
for some reason.
As mentioned, we haven’t changed anything with regards to application configuration. In fact, users that have previously been authenticated and have an active GitLab session can authenticate just fine. Any help would be much appreciated!