If you make use of the source code debugging features WinDBG you may find it quite annoying the way that each time you hit a point in the debug that relates to source in a file you do not already have open WinDBG opens yet another source window. This results in lots of open source windows and a constantly rearranged set of windows.
I found today that if you go into Tools->Options and set the “Reuse after opening this many” option to 1 instead of the default (0):
then what you find is that it will always reuse the same source window to display the currently relevant source.
This mean you can drag the source window outside of the main WinDBG window to a location of your choice (e.g. onto another monitor) and each time a new source file is opened it will open there and not mess up the arrangement of windows in your main WinDBG area.