would there be any use for a "n of m" version? you'd somehow generate m urls, and any n of them would allow you to recover the secret. i guess instead of urls they would be separate parameters, but otherwise it should be doable, right? can't think of any uses, though...
This would be easy to implement via a secret sharing scheme, where shares of the secret are maybe stored in local storage until enough of them are collected in the browser to recover the encryption key. But I can't really think of a compelling use case either.
