The fatal: The current branch master has no upstream branch error occurs when you have not configured git
in such a way that it creates a new branch on the remote. Therefore, you are only creating a new branch on the local computer.
You can fix the issue by typing:
git push -u origin master
This will fix the error, but only for the current issue. The following is a permanent fix that will automatically create a remote branch:
git config --global push.default current
The command above will fix the error and will always create a remote branch that tracks the local branch.
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