HA-Supervised login issue

When I try to login to my HA-Supervised server I get a screenshot as shown. Formatting does seem a bit odd.
I then login and “as far as I can tell” 20 seconds later I am presented with the same login screen. I login again and all is ok.

I dont know exactly when this started but it is most annoying. I am running Debian - Docker and HA-Supervised, so I am reluctant to do a clean install…

Any ideas or suggestions?