I believe it depends on what wall controller you are using. If you have the "smart" ones with the LCD display, clock, temp. readout, etc. it enables the additional security that keeps a contact closure from opening the door. If you use the basic or standard wall controls, it will continue to work with contact closure. We discovered this on a job that had 4 openers in 2 separate garages. For whatever reason, one garage got the fancy wall controls and the other got basic ones. We were able to control the one with the basic controls with a contact closure. The other, we had to get additional controls and solder wires to the button contacts.

YMMV as with anything else. I believe we called tech support for liftmaster and got the above info, as it is not spelled out clearly or at all in the manual for the openers.