Squirrel World is a small Vanilla Survival Server without any plugins, only some command block features like vote rewards or a spawn command. It will always be updated to the latest snapshot version as soon as possible.
The version displayed on this server list usually isn't the real version of this server since it always updates to the latest snapshot.
If your Minecraft crashes: The latest snapshots have a bug which sometimes causes a crash when you join a server. You need to go into a Singleplayer world first, then you can join the server.