Freeing up space · Recycle Vault
Does the Recycle Vault need my external drive connected?
Short answer: For the full safety net, yes. Removed files rest on your external drive; without it they wait on your Mac with a warning and move across when you reconnect. Without any drive you'll see a critical reminder.
For the full safety net, yes. With your external SSD connected, removed files rest on the drive, recoverable for about 6 months. If no drive is connected, Storage Studio holds them on your Mac for the moment, shows a warning, and moves them to the drive automatically when you reconnect it.
Because of that, using Storage Studio without an external drive brings a critical reminder. To restore an item whose files are on the drive, plug the drive in first — the list always shows which items need it. See the on-Mac holding limit.