Have you?
Discussion
I do enough for the both of us.
Girls mostly just clone or fork and change locally, I think. To be less-intrusive.
Then how do you learn what it takes to bring something upstream? We for example encourage our interns to propose changes to open source projects. There is a lot to learn there about how to do things properly. All assuming you don‘t treat GitHub as if it was a GDoc or CMS.
I ask male developers I know to submit for me.
That's what she said?

Well, I like knowing that they also think it's worth submitting and when questions arise, they respond and sound all official and mansplain-y, and I can just lurk.
It's different in my own projects or with some particular developers I have a good rapport with because they're used to me and take me seriously.
Yes. It’s difficult to get developers on other teams to even look at unsolicited pull requests. (The open source world is a different story.) I’ve written extracurricular but unambiguous improvements to my own team’s code, and only the tiny ones have been reviewed.
I've almost done it a few times; write it up and then don't submit.
These days I try to resist even doing the work, because it’s almost always wasted effort.

