Open XLSC file from within Excel

Currently the option [File] -> [Open] is disabled.
Some users have a hard time understanding why this does not work.

Is there a way this can be enabled in a way that a user can load a XLSC file after starting the application?

This is not possible for security reasons and how the application is designed. Moreover, if we allow the Open menu, Excel won’t allow us to override all open options (from local folders, from network…).