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Facebook has rolled out its new hub to help some users figure out if they interacted with Russian propaganda during the 2016 U.S. presidential election.

The social giant’s tool — available here, through its Help Center — specifically allows users to see if they followed or “Liked” any pages and accounts set up by Kremlin-backed trolls on either Facebook or Instagram.

Over the course of the 2016 election, Facebook estimates that roughly 140 million users may have seen Russian propaganda in their News Feeds or on Instagram. Much of that content sought to sow social and political unrest around divisive issues like race, religion and LGBT rights.

But only a small slice of those 140 million affected users can actually take advantage of Facebook’s new tool, which it first previewed in November. That’s because the portal only aids those who directly followed one of the accounts or pages set up by Russian sources on Instagram and Facebook. It does not help users who may have simply seen Kremlin-sponsored content because their friends “Liked” it and it subsequently appeared in their own News Feeds.

Facebook’s new service also doesn’t allow users to check if they saw some of the roughly 3,000 election-timed ads purchased by Russia’s notorious trolls, known as the Internet Research Agency. About 10 million users saw those ads around the election, the company previously has said.

Facebook has said it would be “challenging” to find and notify every single user that may have seen content or ads generated by Russian agents.

Its efforts have nonetheless won it some plaudits from Capitol Hill, where the company’s top lawyer — joined by executives from Google and Twitter — faced a full grilling this November for failing to thwart Russian disinformation online. Exiting a trio of hearings, lawmakers like Democratic Sen. Richard Blumenthal urged all three companies to notify their users about Russian propaganda they may have viewed.

This is Facebook’s attempt to do that, though the company is unveiling the new portal at an interesting time: The Friday before the Christmas holiday, which is usually reserved for unflattering news dumps.

Facebook, however, previously pledged to unveil it before year’s end. And a company spokesperson told Recode that Facebook will promote the portal to users, though it’s unclear how.

For its part, Google told Sen. Blumenthal in a letter earlier this month that the company could not offer similar aid to YouTube users who had watched videos tied to dubious Russian sources. That’s because “content is accessible regardless of whether or not a user is logged in,” Google said, meaning it “would not be able to identify all those who watched a particular video.”

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