External user management option is blocking the editing of internal users

When the External user management option is enabled (under "USERS & SECURITY > Security Configuration"), there's no way to edit the details of a Confluence internal user.

Then option says: Delegate user management to JIRA. More about User Management
However, the internal users are not delegated to JIRA, so we should be able to edit the internal users' details.

Steps to reproduce:

1. Go under the Confluence Admin > USERS & SECURITY section > Security Configuration and click on Edit
2. Check the External user management option
3. Go under Users
4. Find and select the local administrator user
5. Click on Edit Details
6. There's no way to change the details like e-mail and such.

Workaround:

• If you have this option checked, you'll need to uncheck it in order to edit the user. You can check this option again afterwards.