It is a format that is used to easily copy paste the whole data (message + public address + signature) to verify the authenticity of the message.
You can verify those on this page, for example : https://reinproject.org/bitcoin-signature-tool/
I personally find that more convenient than
Message : "blaah"
Address : "1sdfqsfqsf..."
Signature : "qsfjqslkdhfqms..."
Because both signatures couldn't be verified for the accounts staked on the first post. I also found it curious that both messages started and ended the same way but it is most likely a badly done copy paste.