Briefcase and Docker Kobo toolbox

What is the problem? Please be detailed.

I can pull data from Kobo toolbox using ODK birefcase (1.9) no problem.
Using this URL

However when I try to pull data form a local docker Kobo toolbox install it fails with this message

Unable to fetch formList: NOT FOUND (404) while accessing:
Please verify that the URL, your user credentials and your permissions are all correct.If you are behind a proxy, try setting up your proxy details through 'Settings' tab.

The local docker Kobocat is running fine. With no issues.
Any ideas what the issues is?

172.x.x.x is an internal IP address of the Docker container. You'll likely have to connect via localhost:8000 or whatever IP the container exposes to external apps. Might be good to ask the Kobo team for help at