git_record.txt

I ended up doing more improvements to the theme_upgrade2 branch that I don't want to save anything from the master branch. It looks like the strategy to replace the master branch would be this: https://stackoverflow.com/questions/2763006/make-the-current-git-branch-a-master-branch

git checkout better_branch
git merge --strategy=ours master    # keep the content of this branch, but record a merge
git checkout master
git merge better_branch             # fast-forward master up to the merge