This test is only relevant on platforms where it is possible to switch applications in mid-drag (eg. alt+tab, dragging over taskbar buttons, dragging between restored windows).
This testcase requires an external application that accepts dropping of text from other applications - eg. Wordpad (write.exe) on Windows. Ensure that the external application is open.
Select some text in the external application. Drag the selection over the browser window, then back to the other application and release it. Pass if the text you selected appears in the other application.