anchor.diff:    //- - - - - - - - - - - - - - - - - - - - - - -
     // Predict checkbox
   
  +  const settings = cd.settings;
  +  const kata = cd.kata;
  +
     const $predictCheckboxCell = $('#predict-checkbox-cell');
     const $predict = $('#predict-checkbox');
   
  
positive.code:     const $box = $(event.target);
      const colour = $box.data('colour');
      if ($box.is(':checked')) {
        cd.settings.revert(colour, 'on');
      } else {
        cd.settings.revert(colour, 'off');
      }
      cd.kata.editor.refocus();
    });
  
    //- - - - - - - - - - - - - - - - - - - - - - -
    cd.kata.setupPrediction = () => {
      ['red','amber','green'].forEach((colour) => {
        const $box = $(`.revert-checkbox[data-colour=${colour}]`);
        $box.prop('checked', cd.settings.revert(colour) === 'on');
      });
      if (cd.settings.predict() === 'on') {
        predictOn();
      } else {
        predictOff();
  
negative.code:     $buttons.prop('disabled', true );
      const rag = $(event.target).data('colour');
      $predicted.val(rag);
      $revertIfWrong.val(settings.revert(rag));
      kata.runTests(() => $buttons.prop('disabled', false));
    });
  
    //- - - - - - - - - - - - - - - - - - - - - - -
  