I see a secondary source of drinking water. Mmmm buck fresh!
Submitter TurboJens explains this fix: The fill valve split in half and the floater does not cut off the water supply. The towel keeps the water inside and the wrench keeps it from overflowing.
For a few cents more you could buy the fancier, more complex version. It's a little crazy though.
You would scream like that too if you knew the things it's seen.