To add to Yann's answer, once you have forked a project, you can develop in any branch you want (a new one, or one from the original project)
Remember to:
- add the original project as a remote (different form '
origin', since origin would be your own repo, result of the fork)
- rebase your branch on top of the branch of the original repo you want to contribute.
It is important your pulling request result in fast-forward merges.
See for instance:
- "Pull new updates from original Github repository into forked Github repository".
- "Update of forked repository on github"
- "Git working fork with updates"
