for (var i = 0; i < value.length; i++) {
   if (typeof value[i].keyword == 'undefined' || value[i].keyword == null || value[i].keyword.startsWith(keyword)) {
      out.push(value[i]);
   }
}

for (var i = 0; i < value.length; i++) {
     if (typeof value[i].keyword == String(undefined) || value[i].keyword.startsWith("keyword"))
         out.push(value[i]);
}

var out = values.filter(v => v.keyword == null || typeof v.keyword === "string" && v.keyword.startsWith( keyword ));

var out = values.filter(v => v.keyword == null || String(v.keyword).startsWith( keyword ));

var out = values.filter({keyword: v}) => v == null || String(v).startsWith( keyword ));