The big question is do you need X personally? A lot of the time when I contribute to a project it's because I'm using the project and need the feature/bug fix f

The big question is do you need X personally? A lot of the time when I contribute to a project it's because I'm using the project and need the feature/bug fix for the thing I'm actually interested in. In those cases I'll just do it and then send a pull request. Some times they accept it, some times they don't, but in the mean time the thing I'm actually working on has the bug fixes and features I needed. You do however have to be prepared that you will eventually get a No, and then you have to decide if you want to maintain your own fork indefinitely or find another solution (like rewriting your feature as a standalone plugin or library that connects to the project)