This issue only applies to readings, not to meanings. Specifically, readings of kanji with okurigana (the kana that are attached to kanji in certain words, like the しい in 楽しい). I suspect that’s why @NeoArcturus was able to input い. 善悪 has no okurigana, so it won’t trigger the shake.
In any case, to be thorough, I disabled all my scripts.
Still the same message.