Yes. So is Ctrl+J actually. Ctrl+J corresponds to line feed (LF) and Ctrl+M corresponds to carriage return (CR) ASCII characters. They are typically treated the same way.

Yeah, it’s a bit philosophical.
* In graphical applications, Ctrl+M, Ctrl+J and Return/Enter are all different things.
* In a terminal in raw mode, Ctrl+M and Return/Enter are the same thing but Ctrl+J is something different. You can for example run bind -x '"\C-j":"echo a"' in bash and Ctrl+J will do something different.
* In a terminal in canonical mode, they are all the same thing. There probably are some stty options which can change that though.

Right, I must have scrolled past it. I think linking posts is fine. I mean they're public and this is social media... At least I do it somewhat regularly and I've never had anyone complain.

I meant what’s the link to use since the same Lemmy post can be viewed through different instances and on each it has a different URL. It’s a bit user-hostile that the link gets you out of your instance (unless you’re on the same instance as author of the post).

That's right. I don't think there is a good way to do it. I just take whatever link is provided by the small Fediverse icon. But I don't think it matters that much for your audience, they're spread over several instances and it'll be an external link for some of them, no matter what you do. I'm not sure whether we have the ambition to solve this. I don't see anything the user could do. Either this gets handled in some way by the software, or it is how it is.