I was trying to find a way to make apps "data-leak resistant" and one step into this direction was to let the user store the data by bringing his/her own database. I even made a poc https://github.com/andersonDadario/byoda (explanation in the blog post link found on the readme) - but no user would manage his own database. Having a database in the browser opens more possibilities though. I will give it some thought. Looking forward to what else will be built on WASM.
For that to work you won't even need a database in the user's browser - you could just store an encryption key as a cookie today which you use to encrypt all your serverside data when the user logs in
The real problem is how you deal with the average user (who doesn't really backup properly) losing or crashing their device and thus their encryption key/data. You quickly end up with serverside storage and an email-based password reset again...
It's complicated indeed. A simple "clear browsing data" would make him lose the data forever hehe. And if you keep the key in the server, it would be "hackable", which is what I was trying to avoid. I haven't looked at it but https://solid.mit.edu/ looked promising.
