> Though if you're making any attempt to use valid tags you'll have <html lang="ja"> Right, which is why that's a bad example. But it's the same for most "norm

> Though if you're making any attempt to use valid tags you'll have <html lang="ja"> Right, which is why that's a bad example. But it's the same for most "normal" applications (even e.g. text editors, or I remember hitting this kind of thing in WinRAR), and a lot of the time there isn't a standard way of indicating the language/locale in the file. Even within firefox, there are (admittedly rare) cases where you're viewing something that isn't HTML and doesn't have HTTP headers so using the encoding or manually setting the page language is still the only way to make it work - and applications that have a manual "file language" setting are the exception rather than the rule.