Dash in Jupyter tries to bind to $HOST set by conda, cannot override

Summary

Micromamba, and supposedly other python package managers set the HOST environment variable to something like x86_64-conda-linux-gnu. Then, when I try to run a dash app in Jupyter, I get an error as dash tries to bind to host "x86_64-conda-linux-gnu", which obviously doesn't resolve to a valid IP. Here's a stackoverflow post about the error:

https://stackoverflow.com/questions/61006240/name-or-service-not-known-when-running-a-dash-app

In the above case, the solution was to use the host parameter of app.run().
However, the parameter does not seem to override $HOST in a Jupyter environment.

Packages:

dash                 2.18.1
jupyter_client                8.6.3
jupyter_core                  5.7.2
jupyter-events                0.10.0
jupyter-lsp                   2.2.5
jupyter_server                2.14.2
jupyter_server_terminals      0.5.3
jupyterlab                    4.2.5
jupyterlab_pygments           0.3.0
jupyterlab_server             2.27.3
jupyterlab_widgets            3.0.13

Reproduce the issue with Micromamba or another package manager that sets HOST, then run a Dash app in Jupyter and pass an explicit host to app.run(). Trace the Jupyter-specific startup path to identify where HOST takes precedence. Done means the explicit host works in Jupyter despite the environment variable, with a regression test covering that case.