Thread:Project:Support desk/Hiding of non-provided optional parameters/reply (2)

Exactly. I know it can be done, I know part of the theory, but I can't get it to work. As of now I don't have the if conditions because I reverted revisions several times. The problem is that I probably got almost everything right, but there's something missing... Any example of this would help. (I already tried to see similar tables/templates on other wikis, but for the most part it is a mess and I can't find the relevant parts.)