One of the Security options under Options Manager is force_unique_userid. By default, in an out-of-the-box environment, the option is Installed.
Consider the "Important!" note associated with deinstalling/disabling the option. The help for the "force_unique_userid" option is documented as follows:
- Prevents using duplicate active system login names.
Important! We recommend that you keep the force_unique_userid option enabled at all times. If this option is uninstalled, and there are multiple contact records with the same login id, you may experience problems with data partitions, multi-tenancy, security, and other functionality.
The idea here is to remove the option by not allowing it to be de-installed (eventually removing it from Options Manager altogether in future version).
Please reply with any valid use cases for which the ability to deinstall the option is required.