Thanks for the replies. Perhaps my misunderstanding is related to how the versioning notation works or my interpretation of the output.
When I type `jupyter --version` I get back `4.2.1`, which is the version that I reported. When I started the notebook with `jupyter notebook --no-browser` the server output showed (with the token changing each time) :
which created a re-direct (302) to a login page when I tried to open the page in emacs or in the browser (using only
http://localhost:8888).
The emacs notebook developer responded with a workaround so I will try this, and if it doesn't work then I will try the (possibly flawed) solution. Thank you for both the pointer to the documentation, which I think I read but somehow did not understand, as well as the reasoning for the authentication. In my case I primarily use the notebooks as quick sketchbooks where I run the server on the same computer where the client is (and I have the only user account) so hopefully I won't have the security problems mentioned.
In any case, thank you very much for your response.
Best Regards,
Rasso