[NN5I]

Aaargh -- wet carpet at the commode. Lean down, sniff -- whew, it's fresh water.

Remove cowling (one stainless-steel screw) -- it's the shaft seal on the top of the water valve. Hmmm -- looks like really easy to replace.

Ordered new valve, $28 -- and a new flush-valve seal too, $29, since I've got to work on it anyway. Flush-valve (ball valve) seal looks easy too.

Right now the cowling is off and there's a bowl to catch drip under the dripping valve. The drip is very slow. With the bowl there the carpet will dry soon enough.

I'll let y'all know how it turns out.