iMac to Cinema Display : El Capitan 10.11.5

Information:

Discovered that the cord coming from the back of the display for the mini-DisplayPort, that actually has to be plugged into the Lightening Port, can be plugged in upside-down... which renders the display black, until the plug is rotated 180 degrees so as to plug it in the right way. I have a 27" iMac. Interesting to note you can't plug it in upside-down with the MacBook Pro, as the female receptacle is shaped the same as the male plug on the cable (not perfectly rectangular - has 2 beveled corners). What a huge waste of time coming to realize the plug could actually be plugged in upside-down.