I'm not sure I'm following, but is any of this still supposed to work? 1 year after I can't make it work on any major browser, in any of the ways presented, and it's kind of annoying.

It is a very short lifespan for this kind of feature, especially when you see the number of code-centric articles there are on Medium.

You'd expect some kind of support for this very needed feature.

Please, have a look.