I’ve been noticing kanji without vocabs recently, mainly because I was like “huh, can’t really remember that kanji at all…” and when I looked, there was no vocab using that kanji. There’s been a thread here List of kanji with no vocab? from 2017, and one or two similar threads that list a few, but you could probably easily query the API to filter those…
See the solution of that thread, reply #13:
are there any updates on that? Not sure if back in 2017 they were talking about these recent site-redesign-updates? If so, these kanji might soon get some vocabs?
Yeah, that one’d be great… Learning a kanji for lapis lazuli but not the vocab, especially since we know both those kanji but have vocab for neither, makes it seems like these poor kanji have just been forgotten
Also, I assume they are talking about the radical redesign. To be fair, Kristen started adding new kanji and new vocab after that. It’s just that she disappeared before it was all done…
Since things (mnemonic especially) changed, I don’t think they can add it in the current state.