Persistent Menus

From the Viewport toolbar, you can access all the Viewport control menus. However, if you move focus away from an open menu by clicking anywhere within the Application, the menu closes. You can detach an open menu by clicking the top of the menu and dragging it wherever you want it to go:

An un-docked menu is persistent and won't close, even if you move focus to something else. To close a persistent menu, click its "x" icon:

There are a few caveats for using persistent menus:

You can't dock a persistent menu
You can only create one persistent instance of a menu at a time. If you try to un-dock the same menu while a persistent instance is already open, the old instance will be closed.