Most people would immediately call their landlord when their toilet stops working probably. (I think. I don't actually know most people, so this could be a faulty assumption.) Me? Nope. As long as it's quasi-functioning, I muddle-through, telling myself I'll figure out what's wrong with it but lazing out of actually doing it until it stops working entirely. At which point I finally do the requisite Googling, and then realize I'm going to have to call my landlord anyway.
But I have learned a great deal about toilets while Googling, and I figured out a way to jerry-rig my system so that I can trick my toilet into functioning until someone can come and actually fix it. I am posting this knowledge here in case it can help anyone else.
( I didn't know any of this until an hour ago )