For a long time, the Interactions Pane, the Console Pane, Find/Replace, and the Compiler and JUnit Panes were always attached to the bottom of the DrJava main frame. Users who desire the Definitions Pane to be as large as possible, or users with multi-monitor displays, may wish to use the new "Detach Tabbed Panes" option in the "Edit" menu.
When this option is enabled, the tabbed panes will be detached from the bottom of the main frame and displayed freely floating in their own window. The window position is saved, so it's possible to create a nice layout, quit DrJava, and have the same layout restored when DrJava is started again. Another nice side-effect is that all panes can display a lot more items without the need for scrolling. To re-attach the tabbed panes to the DrJava main frame again, simply disable the "Detach Tabbed Panes" option again.
The panes in the free-floating window otherwise behave exactly the same as when they are attached. It's just a different screen layout.