This is useful if we want to expose this service to the Tor network
because browsers usually refuse serving images from https protocol
to insecure http protocol.
The country flag icons no longer use edge.ditatompel.com. It's compiled
to the server binary.
I'm using https://github.com/hampusborgos/country-flags for country flag
svg icons, but the commited svgs was optimized using `svgo`.