[Mazzop]

try

ChatFrame_AddMessageEventFilter("CHAT_MSG_LOOT",function(self,event,msg,who...)
  if who==UnitName("player")
    local id=tonumber(msg:match("|Hitem:(%d+)")) or 0;--    Force nil to zero if we have an invalid link (no items exist at index zero)
    if ItemSetNames[id]  then return false,msg,who.." (|cff9400d3Transmog Sets: "..string.join(", ",unpack(ItemSetNames[id])).."|r).",...; end 
  end
end);