https://www.nuget.org/packages/Preserver.Umbraco/

This package stores state in local storage, then prompts to restore it when returning to the page (ie if the browser crashes, power cut, etc). So no autosave, due to versioning, but enables restoring the unsaved changes. This means that if for any reason we lose the server, the local version can be restored later. This is a property editor for rescuing content changes developed by Nathan Woulfe.