I’m using RIDE to run robot framework. Can it be kept at the top level so that i can monitor the test results without browser windows covering it?
Keeping gui application always on top is a feature of window manager and few other components of your operating system. Thus, making such feature built in into RIDE, while most likely possible, might not be very easy to make it supported in all os’s and desktop environments RIDE runs on…
On linux side, if i remember correctly, certain WM/DE’s should have option to mark the application to be always on top…
As alternative, you could run the browser in headless mode ? 
These days the most productive way to work is to have at least two monitors.
That would solve for now your question.
But rasjani reply is also good.