Ah. Yes "M" it is on my '11.
According to what I've read, if you open the tailgate manually, you just hold it to the desired height and then press the power liftgate button until it chimes, then it will no longer raise higher than your specified position. Should work on all Edges, Escapes, and Explorers with power liftgates. Seems to be mixed on whether they say it works on the Edge though. Never had a reason to try it on mine.