Server-extension example fails because of jupyter-server version

I am trying to understand the server-extension example.

I can’t run the installation steps at the very end of the successfully:

pip install -e .
jupyter labextension develop . --overwrite
jupyter server extension enable jlab_ext_example
jlpm run build

The first step (pip install -e .) uninstalls an existing jupyter_server-2.5.0 and installs jupyter-server-1.24.0. (Why??)

The third step (jupyter server extension enable jlab_ext_example) fails with this output:

File "/home/user/miniconda3/envs/jl1/lib/python3.11/site-packages/jupyter_server_terminals/", line 9, in <module>
    raise RuntimeError("Jupyter Server Terminals requires Jupyter Server 2.0+")
RuntimeError: Jupyter Server Terminals requires Jupyter Server 2.0+

Only when I remove jupyter-server-1.24.0 and install jupyter_server-2.5.0 again, and then repeat steps 2-4, can I run the example.

Where is the dependency on jupyter-server-1.24.0 introduced, and how can I experiment with the example without fixing the jupyter-server after each pip install?

Thank you