Setting frontend.base_url

[kmbae]

Description

I just wonder about setting the base_url for the jupyverse.
For instance, when running jupyter lab, the --LabApp.base_url option modifies the URL while connecting via browser.
I thought that --set frontend.base_url=/test/ works the same as --LabApp.base_url=/test.
But this option does not behave as I expected. Any solutions?

Reproduce

1. Run jupyverse using below code
   jupyverse --set kernels.require_yjs=true --set jupyterlab.server_side_execution=true --set auth.mode=noauth --set frontend.collaborative=true --set frontend.base_url=/ --host 0.0.0.0 --port 8888 --allow-origin '*'

2. access the jupyverse using browser and obtained below screen.
   http://ipaddr:8888/lab

3. Run jupyverse using below code with base_url option
   jupyverse --set kernels.require_yjs=true --set jupyterlab.server_side_execution=true --set auth.mode=noauth --set frontend.collaborative=true --set frontend.base_url=/test/ --host 0.0.0.0 --port 8888 --allow-origin '*'

4. access the jupyverse using browser and obtained below screen.
   http://ipaddr:8888/test/lab

Expected behavior

Expected to have the same screenshot for both options.

Context

• Operating System and version:
• Browser and version:
• Jupyter Server version:

Troubleshoot Output

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You may want to sanitize the paths in the output.

Command Line Output

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Browser Output

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