Lab extension installation by users on jupyter hub

Hi, we are using jupyterlab on jupyterhub. Do anyone knows whether it is possible for non admin user to install a lab extension (like they do for kernels)?

thanks

As of writing with jupyterlab 3+ it sounds possible judging by this closed github issue/thread. I have not figured out the magic command(s) to get it done though, and the current documentation is not helping in this presumably essential use case. So far as I can tell the closest guess was jupyter labextension install --app-dir /home/jovyan/.jupyter/lab/ bqplot and this installs quite a few extra things under that folder, but the system-wide jupyterlab upon restart still does not register the lab extension.