When entering a single-word domain (ie. `example/`, `http://example/` or `http://example:8080`), in Safari on macOS, Safari will *sometimes* change it to http://www.example.com. I suspect this is a feature designed to help inapt users, but it kicks in at unwanted times, and I don't want this feature!

It seems like this is dependent on some kind of caching (possibly DNS), so that if Safari first decides to change it, it will keep changing it no matter how many times I type it correctly. But after maybe a few hours, it will do as I expect.

How do I disable this pesky "smart URL conversion" feature?