I asked this before and now cannot find the answer or even my question. (Why is SW so non-intuitive and hard to navigate?) I archived a conversation with a view to deleting it, but now count find it.
@Sniper OK, I followed the advice of SodaPressed and went to Account Settings to find Archived Messages. I clicked on the last post on the conversation I wanted to delete and a trash bin icon appeared. I clicked on that and, after, a warning that it was irreversible, I was able to delete the whole thing.
