For regular chat feeds, if a question has more than one tag for which a subscription has been made for a feed, the question still only gets one-boxed once.

However for ticker feeds the question seems to get duplicated as in this example:

Here's an example where the item was triplicated:

For people that have had the room open in a tab for a whole day while working on things in other tabs, the list can get quite long. The room from which I took these examples is this one.

Prior research before asking: I searched here on Meta.SE but only 10 questions had been asked about ticker feeds and none of them are about this duplication of items.