code: function(v) {
              var $formBody = $("td.ms-formbody, td.ms-formbodysurvey"),
                  // Borrowed from MDN.
                  // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
                  escapeRegExp = function (v){
                      return v.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, "\\$1");
                  },
                  columnName = escapeRegExp(v),
                  rcommentValidation = new RegExp("(?:Field|FieldInternal)Name=\"" + columnName + "\"", "i"),
                  $columnNode = $formBody.contents().filter(function () {
                      return this.nodeType === 8 && rcommentValidation.test(this.nodeValue);
                  })
  
              ;
  
              return $columnNode.parent("td");
          }
docs: Finds the td which contains a form field in default forms using the comment which contains: <!--  FieldName="Title" FieldInternalName="Title" FieldType="SPFieldText" --> as the "anchor" to find it. Necessary because SharePoint doesn't give all field types ids or specific classes.