When you create a new User Group, select a site template (either public or private pages), and disable propagation of changes from the site template, you get a null pointer exception in the console and a "User Groups is temporarily unavailable" error message in the browser.

If you navigate back to the user group that was created, the site template that was selected under Public/Private Pages is not saved.

1. Navigate to Control Panel > User Groups
2. Click Add to create a new user group called Test User Group
3. Under Public Pages, select Community Site
4. Uncheck the "Enable propagation of changes from the site template Community Site" checkbox
5. Click Save