He was told by the original author to not use the name for his project 5 days ago. 3 days ago he wrote "Guys, all I wanted to do is to make Notepad++ available on mac and keep it open and free. I'm talking to Don. I really hope he will be ok with the name. It actually expands notepad++ brand to mac."

Already ignoring the authors wishes. He said clearly it is not OK and wants the name changed. That's it - but he keeps ignoring it.

I fail to see good intentions here.

Yeah. And if you want to expand an existing brand that's not yours, you ask first, and only continue after a green light from the owner.

Well, that part might be temporarily excused by naivety. But he did ask, was not replied to - and he did it anyway. So I actually do not believe in naivety. And now it is past that point anyway.

You mean asking for forgiveness is easier than asking for permission is not a valid way to walk through life?

In general really no, but I do see the point in not asking for permission for everything to get anything done. (I am german, here the saying is, anything not explicitely allowed is forbidden and there is no fun in this)

But I hate the stance when people do it, when it is clear that no permission will be given. To establish facts on the ground so to say.

(But there are exceptions where I think it is legit)

Judging by the fork author's name, should've asked them in russian :-/