NotebookApp Error unpacking user from cookie

**Describe the bug**/ **To Reproduce**

🚫 When I launch notebook from terminal, it keeps giving `forbidden` error, when trying to save
(in the title, the error message in console, with many 403 warnings)

✅ it works fine though if I `launch classical notebook` from `jupyter lab`

**Desktop (please complete the following information):**

- OS: macOS 13.0
- Browser: brave, safari

some relevant packages from my `pip freeze`
```
ipykernel==6.20.2
ipython==8.8.0
ipython-genutils==0.2.0

jupyter==1.0.0
jupyter-console==6.4.4
jupyter-contrib-core==0.3.3
jupyter-contrib-nbextensions==0.5.1
jupyter-events==0.6.3
jupyter-highlight-selected-word==0.2.0
jupyter-latex-envs==1.4.6
jupyter-nbextensions-configurator==0.4.1
jupyter-server-mathjax==0.2.6
jupyter_client==7.4.9
jupyter_core==5.1.3
jupyter_server==2.1.0
jupyter_server_terminals==0.4.4
jupyterlab-pygments==0.2.2
jupyterlab-widgets==1.1.1
jupyterlab_server==2.19.0
jupyterlab==3.5.2
```

Start by reproducing the terminal-launched NotebookApp behavior and compare it with launching the classical notebook from JupyterLab. Trace the cookie user-unpacking path associated with the 403 save warnings; done means saving works without the forbidden response and the regression is covered by an appropriate test.

Written by the indexing model from the issue text.