edit

stash edit <shortname> [-t/--title <TITLE>]

Without --title, opens the item in $EDITOR. If the content changes, the previous version is automatically saved to history before the update is written.

With --title <TITLE>, updates the title only without opening an editor. The current content and old title are archived to history as part of the update.

stash edit todo                       # opens $EDITOR
stash edit gh --title "GitHub Home"   # title-only update

See also history / restore for reviewing and undoing edits.