An old post can be flagged at any time, so the queue is reloaded rather than added to.
ProtectedinsertProtectedmatchesA new reply has no flags yet.
ProtectedmayWhether a new discussion's first post might belong here: false rules it out.
ProtectednewerA new reply that certainly belongs here is inserted from the payload; one that certainly doesn't is ignored; only undecidable ones ask the server. A new discussion's first post isn't in its Started payload, so a column that may want it asks.
ProtectedprepareRuns once before the first load, for columns whose params need looking up.
A post whose flags were dismissed, here or elsewhere, leaves.
ProtectedrefillFor a prune() that takes posts out: the next page fills an emptied column.
ProtectedremoveProtectedshownProtectedshowsProtectedsnapshot
Posts with open flags, most recently flagged first, each with Flags' own flag bar to act on. The server decides what's listed, so only flags the member may see ever appear.