The bug is not present in the original LSM data (as I showed in another comment), but is present in the JSON data¹:
{"author":"Manuel.Serrano@inria.fr (Manuel Serrano)","primary-site":"ftp.inria.fr /INRIA/Projects/icsla4048000 bigloo1.3b.tar.Z\n","maintained-by":"Manuel.Serrano@inria.fr","entered-date":"1996-01-01","version":"1.3","keywords":"","original-site":"","description":"Bigloo is both a interpreter and a compiler. It is conformantto IEEE Scheme standard with some extensions from which we can\nsite regular parsing or pattern matching.\n","copying-policy":"Copyleft","platforms":"","alternate-site":"","title":"\"Bigloo, a Scheme to C compiler\""}
You can see that the same bug is also affecting other multi-line fields, like “Primary-site” here, and “Alternate-site” for other projects.
Sorry, the point of my post was supposed to be "it's a new project and they're probably busy, hence one project conserved." Wasn't trying to disparage you at all.
Actually, I already provide this in the release notes. A PROTOCOL_VERSION bump means restarting tmux. We didn't do this between 1.9a -> 2.0, hence why it wasn't mentioned. Look at the release notes for 1.9, you'll see it was mentioned there. Simples.
Some of the information is out-dated yes, you'd expect that. Especially when people were asking for help about dial-up modems, for example.
But I bet if you were to try some of the other stuff on there, it would still work today...