Up until v9.5.9 we had a working omniauth provider to allow users to login to GItlab via our own oauth2 server. After upgrading to Gitlab v10.3.3 the integration no longer works.
The error we get is:
Could not authenticate you from OurAuth because "Invalid client: client authentication failed. {"error":"invalid client","error description":"client authentication failed."}".
This is the only method to login to the server. I’m not sure where to begin in trying to resolve this issue. But I suspect that our custom omniauth strategy is no longer compatible.
Is there anyone that might have some knowledge of using omniauth and custom strategies with Gitlab?