Administration - Installation - Core: Menu and some buttons missing in 6.1 / Docker

I am wondering if anyone has ever seen the main menu go missing before?

I do have a custom skin, but no mainMenu Plugin.  Also, even when I disable the custom skin, the menu does not return.

I have one installation of version 6.0 (which I upgraded from 5.X) with my custom skin installed.  6.0 is as I expect it.
I have a 2nd installation of version 6.1 which I installed via the docker image https://hub.docker.com/r/sturai/ilias/.  The main menu does not render and some buttons are missing.

Does anyone have an advice on how to diagnose this?

Thank you in advance!
--Jason