Facebook Inc. on Wednesday said it plans to tell millions of users who liked or followed any of the 290 Facebook and Instagram pages created by Russian actors that they were ensnared in an alleged misinformation campaign around the U.S. presidential election last year.

Yet the disclosure falls short of notifying more than 100 million other users who came across the pages’ ads and posts, and may have liked, shared or commented on them. And it provides little information to those users who did follow the pages.

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