What Save actually keeps
The Save button remembers a production in this browser. It does not download a movie file, subtitle pack or application. Your list remains useful for planning a trip, but you still need to arrange the actual viewing edition separately if the destination will have no connection.
Offline viewing belongs to the selected service
Where a service offers downloads, inspect its plan, device support and expiry rules. Some downloads remain playable only in its own app, and a rental can have a limited viewing window. Check those details before relying on the film during travel. One title being downloadable does not establish the same option for every film in the catalog.
A list backup is deliberately small
Our backup is text describing saved references and supported episode checkpoints. It is not a disguised media archive. Copy it to a place you control, then merge it in the other browser to recover your shortlist. The backup instructions explain the result messages and what happens to existing checkpoints.