Hi, Nomad :O)
We have been using spray-on bathroom cleaner with mildew killing ingredients. Even the refrigerator handle, which is kind of a soft plastic, seems to harbor mildew. This takes care of it. I think any brand would do. husband bought something at the Dollar Store because someone native to here recommended the bathroom cleaner with mildew killer.
It works great for lawn furniture, the tops of convertibles, boat seats, sometimes even grout, if the problem is mildew.
Another really good cleaning tool is rubbing alcohol. (Not for mildew.) Dilute it with water and a tiny drop of Dawn. Granite, faucets, windows, appliances, mirrors ~ the solution cuts through grease and leaves no streaks.
Fingernail polish remover will take off residue from stickers.
Hairspray will take ink out of fabric or leather.
Cedar