(double posting for visibility, since we’ve been on a closed GitHub issue)
The jupyterhub sphinx theme has SVG logos here. There’s even a dark-theme filename to make the theme work, but it’s not actually different, so that would be the place to put an updated dark-background colorway, and we can copy it into JupyterHub itself once you’ve done the work there.
Hi @minrk
In the link you shared, the “hub-rectangle-dark.svg”, is almost correct, just the one circle in the bottom left of the Jupyter moon needs to be completely white - as mentioned in the Jupyter brand guidelines doc.
You can read more about creating a pull request, or for small edits like this, you can click the edit button when viewing the file and paste your new SVG in there, and it should take you through the steps: