As another comment pointed out, the actual title of this article is ‘Oumuamua, Thin Films and Lightsails. While the question "Could ‘Oumuamua be debris from a technological civilization, a discarded lightsail?" occurs in the article, this title does the article a clickbaiting disservice.

("Is the interstellar object Oumuamua a lightsail from an alien civilization? " at the time of this comment)