Description
Currently, mei-friend tracks all changes to the encoding, as well as most settings, layout options, etc. in the browser's local storage, so that the application may be reinstated after browser shutdown, etc. Unfortunately, this means that there is currently a baked-in assumption of a single current session. It would clearly be preferable if multiple concurrent sessions (e.g., working on multiple MEI files simultaneously in separate tabs) could be accommodated.

Proposed solution

• Generate a unique identifier for each new session, defined when an encoding file is opened.
• Prefix all local storage variables with this identifier, allowing multiple versions to exist in local storage simultaneously.
• Use the browser's session storage to store the current session identifier.
• When loading MEI friend, check for the existence of a session identifier in the session storage. I
  • if it exists, check for the existence of corresponding items in the local storage and load them
  • if it doesn't exist, or corresponding items don't exist in the local storage, offer the user a selection of known sessions (also stored in local storage) to load, or the option to start a new session.

This solution would allow multiple sessions to co-exist on the same machine.

Additional context
Whenever anything is written to local storage, it would need to be prefixed with the new session variable.
Note that local storage is only capable of storing strings, therefore serialization needs to take place.