code: function() {
              // If lockup is already locked don't try to disable inputs again
              if (this.$pinny.lockup('isLocked')) {
                  return;
              }
  
              var $focusableElements = $(FOCUSABLE_ELEMENTS).not(function() {
                  return $(this).isChildOf('.' + classes.PINNY);
              });
  
              $focusableElements.each(function(_, el) {
                  var $el = $(el);
                  var currentTabIndex = $el.attr('tabindex') || 0;
  
                  $el
                      .attr('data-orig-tabindex', currentTabIndex)
                      .attr('tabindex', '-1');
              });
          }
docs: Traps any tabbing within the visible Pinny window
  by disabling tabbing into all inputs outside of
  pinny using a negative tabindex.