When trying to log in as a user without groups and with applications access in one or more applications, the user is redirected to the system dashboard URL with a message that he/she is not logged in and when clicking on the 'Log In' link in the top right of the screen - it keeps redirecting to the same page (dashboard).
This issue is a failure of handling no-group user accounts to prevent extreme confusion.
Please, see steps to reproduce below:
1. Create user and take him off of all groups
2. Grant him application access in one or more applications
3. Now, try to log in with this user
4. Get redirected to the dashboard page, with a message that you are not logged in and when clicking on the 'Log In' link in the top right of the screen - it just refreshes the page.