I'm now actively working on this for 3.6.

I've attached my first pass at implementing an alternative raw IO stream that uses the *ConsoleW APIs instead of the CRT. It works fine for basic print() and input() (including handling redirection "properly", which is a separate issue to change the default encoding there, and not issue17620 yet).

I expect there to be many *many* compatibility issues with this change, so we really need everyone interested to try it out and see what doesn't work. So far I haven't even tried looking at readline hooks or similar (though maybe all those issues fall under issue17620?).

Any *specific, technical* information about compatibility issues would be appreciated (i.e. enough that I can fix the issue without having to completely reproduce your setup - I'll be working on doing those myself anyway, so simply saying "X is broken" isn't helpful yet).

It doesn't look like this will be available in 3.6.0a4, but I think I should be able to land it by the first beta.