I just pushed a small update to the component.
This should be fixed with the above. I’m really sorry it took so long to get a fix in place. Thanks again for your report!
You will need to add /login to the url must contain theme setting. See this post for more detail.
This has been reported once or twice in the past. Unfortunately I have never able to reproduce it. I’ll try again when I get a chance using your exact steps and see if I have any luck.