I've noticed that when I try to sign in to Omni via the home page (
https://www.omnimaga.org/index.php ), it just hangs with a "Loading..." status bar at the top and never actually logs in. However, when I navigate to any other page and try to log in at the top, it works fine.
It has happened to me a few times in the past, but I so rarely need to log in that I attributed it to my internet connection.