Navigation module clashes with Admin Toolbar Extra Tools

Problem/Motivation

When Navigation is enabled on a site where Admin Toolbar Extra Tools is used, some of the 'Create' menu links appear at the top level instead of the second level. This is fixed by uninstalling Admin Toolbar Extra Tools.

Before:

After:

Steps to reproduce

Enable navigation menu on a site where Admin Toolbar Extra Tools is already enabled

Proposed resolution

Document that Admin Toolbar Extra Tools should be uninstalled before installing Navigation?

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet