UI11 was deprecated in the Istanbul release, and should not be used any more.
To ensure that users can use the latest User Interface set the glide.ui.doctype property to true. To move users away from UI11, update sys_user_preferences glide.ui11.use to false for all users.
Time to fix
This rule is linked to Common Weakness Enumeration CWE-150 Improper Neutralization of Escape.