The top toolbar can be set to be "Active" or "Inactive" when you have an RO open. When the toolbar is active you can navigate to your Quick Picks, Customer, Parts, etc. tabs and check other things, then return back to your RO without having to close the window. When it is "Inactive" you will not be able to use these tabs and your RO window will have to be closed before moving forward. 

The setting that causes this to be "Inactive" is in your Setups > This Workstation Setup. On the first page of This Workstation Setup, at the bottom of the Miscellaneous Setups you will see "This workstation uses a small monitor (1366x768 or smaller)" If this setting is checked, your toolbar will become "Inactive" when you have an RO window open. 

To activate your toolbar while having a RO open, simply uncheck this box and save. You will then be able to navigate your toolbar while having an RO window open.