On the topic of scripts to add, I personally find Wanikani aggravating without a way to ignore/change wrong answers ([Userscript]: Double-Check (Version 2.x)), but there is a big caveat. Only get this if you can trust yourself to not get tempted to cheat. You spelled a Japanese word wrong (including something as small as forgetting a long vowel?), you were wrong, be glad the extra lessons will fix that. Mix up the meaning? Wrong.
That said, while Wanikani checks for typos in English answers, that isn’t perfect, and if you aren’t super careful, a Japanese typo can happen too. Real typos can get ignored and fixed. Or sometimes you’ll know that you knew the English answer but your mind was swirling around the meaning and didn’t latch exactly onto the specific English phrasing Wanikani wants – make sure you were REALLY right and not “close enough”, but it sure does happen. User added synonyms exist to somewhat alleviate the meaning issue, but that’s a retroactive fix and I personally like not having to worry too much about adding them vs just recognizing I entered something I might have considered a synonym anyway. That doesn’t even happen that often, but I’ve gotten things like “to whisper in the ear” (might have been slightly different phrasing, I don’t recall what I typed exactly) or something marked wrong because it wasn’t “whisper in ear,” or I got lazy and typed “cow meat” instead of beef and wanikani didn’t like that.
Just be disciplined if you do use this, don’t let me ruin your learning by sharing it. I just know some people find the incorrects that should actually be correct to be really frustrating. I certainly do.