That’s impossible, look up the Halting problem

But it is also a fun road!

It depends how you use it. There is no requirement as to how you set up your directory structure, so you could have one file “passwords” with all your credentials in, including the website. That would break a lot of plugin’s functionality though.

Unraid is not a backup. It is good, but if your data goes wrong for different reasons or you lose the entire device, you can’t restore it. Dedicated backups are a must for anything serious!

To be fair there is so much JPEG compression on the image, you can’t see much of anything.