Floating a window
A window pane is a dockable window. When you "dock" a window pane you position it along the edge of another window or pane. When you "float" a docked window pane, you move it so that it is no longer positioned along the edge of another window or pane.
To "float" a tabbed window in the workspace (for example an instance of Vizex) right-click on the window tab and select Float from the right-click menu.
The window can now be docked like any other window pane. See: Docking a window pane
To make the Vizex window a tabbed window again, simply right-click the down arrow button on the title bar and toggle off the Dockable property of the window: