Create an orphan branch without checking it out

git-branch-orphan.ps1

git stash                             # 1. save index changes
git rm -r --cached .                  # 2. empty the index
git branch orphan (                   # 5. create the orphan branch
  git commit-tree -m 'Empty commit' ( # 4. commit the empty tree
    git write-tree))                  # 3. write the empty index
git reset HEAD                        # 6. revert emptying of the index
git stash pop --index                 # 7. restore stashed changes