code: function _Overlay_showAndHideFast(showCommands, hideCommands) {
                      var count;
                      var command;
                      for (count = 0; count < showCommands.length; count++) {
                          command = showCommands[count];
                          if (command && command.style) {
                              command.style.visibility = "";
                              command.style.display = "";
                          }
                      }
                      for (count = 0; count < hideCommands.length; count++) {
                          command = hideCommands[count];
                          if (command && command.style) {
                              command.style.visibility = "hidden";
                              command.style.display = "none";
                          }
                      }
  
                      this._commandsUpdated();
  
                  }
docs: show/hide commands without doing any animation.