[chrismorgan]

It is interesting to note that YouTube now inserts an interstitial “you are leaving YouTube” screen on its open redirect spot.

That Reddit shows the domain name next to the link (HN also) is, I think, the key here—it casually set expectations. Most link situations won’t be like that, and so I’m broadly with tptacek, that it’s not actually so useful. Plus, businesses commonly use all sorts of different domains, rather than subdomains, and something like yourbank-security.com instead of yourbank.com may not even raise eyebrows—to say nothing of people probably not even twitching at login.yourbank.com.evil.com anyway.