str = "How can mirrors be real if our eyes aren't real";
Test.assert_equals(str.toJadenCase(), "How Can Mirrors Be Real If Our Eyes Aren't Real")

I'm assuming the Python version since that's what the email linked to. Either way, the example test fixture should be roughly the same for every language. As a courtesy, you could try to reset your browser cache to determine whether that works, and then file a bug with Codewars describing the issue.

str = "How can mirrors be real if our eyes aren't real"
test.assert_equals(toJadenCase(str), "How Can Mirrors Be Real If Our Eyes Aren't Real")