Definitely looks like a drain fly. I've seen them before although I have not had them with my current bin. I am a strong proponent of keeping netting over the bin and it's been successful for me with eliminating fungus gnats and fruit flies. It certainly seems worth a try.

I am setting that up ASAP. Thanks.

I'm not sure I mentioned it anywhere in the other topic, but it also helps to have a good vacuum cleaner deployed nearby at all times. The netting won't kill any flying critters, it just prevents them from getting back in after they fly out...and once they're out, they'll still be in your space. You can lift up the netting periodically and vacuum out the flying beasties, and vacuum up any loose flies that may be around lights or wherever they tend to land. Since my bin is in my basement I kept my big Shop Vac nearby and plugged in.

I don't have enough to warrant a vacuum yet, but once I do, I will definitely take advice! Thanks!