It doesn't seem to like non-ascii characters.
"ěščřžý";
"привіт";
"<emoji><emoji>"; // HN stripped the actual emojis
turns into:
"undefinedundefinedundefinedundefinedundefinedundefined";</br>
"undefinedundefinedundefinedundefinedundefinedundefined";</br>
"undefinedundefinedundefinedundefined";
