The article is about accessing a service (nostr) through a hosted web app. The domain or server that is hosting the app could be compromised and serve a bad app

The article is about accessing a service (nostr) through a hosted web app. The domain or server that is hosting the app could be compromised and serve a bad app. Posts on nostr use a key pair so when you see a post from foo you know it's the same foo you knew from last week. Also, posts are shared to and stored on multiple independent servers (called relays). A compromised app could serve you fake posts or censor stuff.