In a repository with no "master" branch, trying to initialize git flow fails with this unhelpful error:

Using default branch names.
Which branch should be used for bringing forth production releases?
   - develop
Branch name for production releases: [] 
Local branch '' does not exist.
Completed with errors, see above.

In Bitbucket, I've set "main branch" in our repositories to be "develop", so when we clone we get a local develop branch but no master branch. So, initializing Git Flow fails unless we manually create a master branch first.