Want to get a breakdown of the vocab from the review screen? Hover over a kanji, get its meaning.
Currently will show even before answering. Don’t cheat 
06/08/2018 Update: Tooltips only exist after answering, and only on meaning. Couple options added. ‘Auto-show’, and ‘Only (auto-show) On Wrong’. Formatting changed as well to make multiple tooltips being open at the same time not look terrible. Enjoy, the two people who’ve installed this, if you’re even still using it.
Is this intended to be a companion to the Fast Abridged Wrong Answer (or whatever it was called, haha) script, intended to make it so that you don’t have to open the item info?
Pretty much. Save a small amount of time not having to click, and look all the way in bottom left-hand corner.
Originally thought about making this an addition to Fast Abridged, but that doesn’t need APIv2 stuff, whereas this one does.
It would be nice to add the ability to auto-pop all the tooltips, but that gets tricky with overlays. Could alternate top/bottom, but I’m sure some have super-long answers… Max-width with wrapping as well? I’m sure I’ll find some time to play eventually.