カレンダープラグインのオプション検索結果が正しい場所に表示されない

That’s because Footnotes does not have its own custom admin plugin UI page like Calendar does:

Really the fix here is to make Calendar match plugins like AI and Gamification that have the new plugin UI and have the Settings tab in the same place. From our internal topic (t/122601), these are the plugins that still aren’t done: