Hey, fantastic userscript!!
I just have one small feature request: in the interest of making the display more neat and tidy, could we maybe get an option to disable/hide the “label” part? (i.e. the “丸 ⇔ 九,” “on ⇔ kun,” etc.)
Mousing over could still provide a breakdown of what exactly went wrong, but I feel like 99% of the time, I can already tell what went wrong simply by looking at what’s in the list (at which point, the labels are just visual clutter).