There is no built-in persistent storage feature, however you can use your own storage implementation.
State Management Libraries
Check the pinia example to see how to use Vue Flow with a state management library.
This example demonstrates save & restore functionality using the
LocalStorage of the browser.
You can extend on this basic idea however you like, i.e. fetch data that you transform into elements which are then passed to Vue Flow or some other business logic you would like to handle.