I've seen .: used two times now, and I really wonder what is? The first time I saw it was in an extract from the Swedish dictionary SAOL in NE. They used it something like this so:
I can see 4 top level comments earlier than yours that address the OP, without being involved in the ie eg debate. I'm on the same instance as you too so idk why you wouldn't see them. caching problems with your app or browser?