Answer by Ka Wa Yip for How to remove password for Jupyter Notebooks and set token again

If you are using JupyterLab instead of jupyter notebook, you need to go to the folder where the jupyter_server_config.json is stored. For my case it is stored in /Users/username/.jupyter.

Then change the password to an empty string by:"password": ""

Save the file and you can open JupyterLab without a password.