What
Claude Code keeps backups of files it edits so you can undo changes with /rewind. When it makes the first backup of a file, it can now record the real folder the file sits in and that folder's identity. Then:
- If the folder changes while the backup is being taken, the backup is aborted and the partial copy is removed.
- If a folder above the file is a broken shortcut (a symlink that points at nothing), the backup is refused.
A new message can appear when you try to restore too soon: "The file backups are still being copied. Nothing was changed. Try again in a moment."
This behaviour is controlled by a switch the server can turn on.
Why
It closes a gap where a folder swapped in at the wrong moment could send a backup to the wrong place. When the check is active, a backup that would have been unsafe is recorded as a failure instead.
Names in the bundle/rewind