Board Thread:Support Requests - Getting Technical/@comment-46539204-20200910182111/@comment-9605025-20200910233114

What do you mean by "global"? There is not way to make a change to your message wall on one wiki and have it automatically transfer to all other wikis. The closest you can get is using scary (i.e. interwiki) transclusion to replicate whatever you have here on Community Central. However, even then, I still don't understand what it is you are trying to customize. If you are trying to customize your wall greeting, then you should be aware that wall greetings don't exist on UCP.