Pisound docs not working on High Sierra Mac

For some obscure reason, I can run Midihub docs on my 6,2 MacBook Pro, but not Pisound docs. I get this:

[12:50:36][stuart@MacBook-Pro:~/Data/Music/Audio Software/Pisound/pisound-docs]$ mkdocs serve
INFO - Building documentation…
WARNING - Config value: ‘google_analytics’. Warning: The configuration option google_analytics has been deprecated and will be removed in a future release of MkDocs. See the options
available on your theme for an alternative.
INFO - Cleaning site directory
.icons/.svg
[12:50:53][stuart@MacBook-Pro:~/Data/Music/Audio Software/Pisound/pisound-docs]$

@stuzog which version of mkdocs and mkdocs-material are you using? we are using mkdocs==1.1.2 and mkdocs-material==5.5.12 to generate our documentation.

mkdocs 1.2.2
mkdocs_material-7.2.5

Also
mkdocs_material_extensions-1.0.1
mkdocs_redirects-1.0.3

Installed with Homebrew