Which Minecraft versions does Welcome Message support?
Welcome Message sends a user who joins your server a welcome message, with customizable color and an option to specify sender.
CurseForgemod
No published Minecraft release
Welcome Message has not published for any Minecraft release we can read.
One mod is never the whole story
A modpack can only move to a new Minecraft version when every mod in it has. McPackSmith reads your whole pack and tells you which ones have not caught up - and Welcome Message is only one of them.