Strange behavior with $.unique()

Strange behavior with $.unique()

The doc on $.unique() states thus:
Description: Sorts an array of DOM elements, in place, with the duplicates removed. Note that this only works on arrays of DOM elements, not strings or numbers.

..... This function only works on plain JavaScript arrays of DOM elements, and is chiefly used internally by jQuery. You probably will never need to use it.
I don't use this function; I have never needed to use it. However, I happened to be playing around with it and discovered something very strange. The array below is not of DOM elements so I was not expecting it to even work half the way it did. Maybe that's why we are kind off encouraged not to use it.

Look at this code:

  1.     var frmElms = $('#myform').find('select,input,textarea').map(function() {
  2.         return this.name;
  3.     });
  4.     console.log( frmElms );
  5.     $.unique( frmElms );
  6.     console.log( frmElms );

Let's say in line 1 frmElms = [ "q0", "q1", "q1", "q2", "q2", "fn" ]. Now  take a wild guess. What do you think would be the output in line 4? Are you sure? How about line 6? Feel free to post your guesses for these two lines in your response.

Now click here (WAIT, did you complete the assignment above?), note down the console output, then uncomment the commented line. Click Run and note down the console output. Can anyone explain what's going on here? A setTimeout delay of at least 510 approx. (not conclusive) of the lines 5 & 6 above seemed to even out things.