не работает если массив большой и имеет несколько пустых строк, пробелов

Marry me

Nice.

Note that the similar function here has O(x*y) performance.

A easy O(x log(x)+y log(y)) performance solution is possible, and a O(x+y) too :)

Me too :/

@smolen,

Many thanks for reporting this issue, I have just tried the Kata myself and found it throwing the very same error which is weird because I have not encountered this error before in this Kata and I do not recall editing the Kata in any way ever since it was approved (which it did not have issues back then). I believe that some update on Codewars (perhaps regarding JavaScript language versions) broke this Kata. I will investigate this issue in due time.

Cheers,
donaldsebleung

I have the same issue.

No matter what solution I try I get:

throw "toUpperCase() has been disabled for the purposes of this exercise";
^

I am not using toUpperCase.

Your uniq 1 answer definitely changed the way I approached the last two. kudos!
Our uniq 3 solution is nearly identically, though I also didn't know about Object.is :)