I am not sure what happened, but when user tries to open a notebook in https://jupyter.oneapi.devcloud.intel.com/user/tree, it gives a 500 Internal Error. Moreover autocompletion (pressing tab after object.) won't work. I've tried with jupyterhub and SSH tunelling, in both cases jupyter autocompletion won't work and extension manager gives the same error (Error: 500 (Internal Server Error)).
Thanks for reaching out to us.
We understand your concern. Internal server error while loading the jupyter notebook will be a temporary issue.
Here are three ways to workaround this error:
1) Delete the cookies for devcloud.intel.com from your web browser. or
2) Use a private browsing window or
3) Use a different browser
If the issue still persists, please let us know.