You might need to restart your browser after fixing the problem with a missing home group.
It’s interesting that this was the root cause of the problem since with your earlier error log, it looks like we can do better in terms of how we handle that issue. I’ve created a GitHub issue to track that idea: Add warning log when a database from KPRPC is null · Issue #308 · kee-org/browser-addon · GitHub
Coincidentally, the stability improvement I’ve just released in Kee 3.8 beta should help reduce instances where the matched logins view is empty. It’s only going to help with a small number of websites in normal usage but could be helpful for all websites if earlier errors (such as a missing home group) have forced Kee into a broken state.
So if a browser restart doesn’t help, you definitely should install the latest beta and try again with that.