'cause the j́ (j with an acute) isn't actually a proper char in unicode (it even renders incorrectly on this site lol), and it is very sometimes used!!

like very sometimes lol, you can place acutes on vowels to put emphasis on them or to distuingish them from homographs, but since <ij> is technically a vowel in dutch, you sometimes want to emphasise it, leading to íj́ lol