Facebook and its Silicon Valley social media rivals are once again in "we'll do better" mode after offering their largest figures yet on the hundreds of millions of users exposed to Russian troll farms' fake news. 

Facebook general counsel's planned testimony for Tuesday and Wednesday shows them revealing an even higher number of people -- 126 million -- who were potentially shown Russian-backed fake account content. Between 2015 and 2017, the social media giant has struggled immensely to rebuff fake news that hit users' newsfeeds during the contentious 2016 U.S. presidential election. The very term "fake news" became a buzzword after then-presidential candidate Donald Trump began touting it at campaign rallies and debates.

The video above contains some of the most widely shared fake news headlines that have swirled across Facebook newsfeeds since 2015. Politically, the ads targeted both liberal and conservative figures.

Facebook and fake news have a long and tumultuous history of coexistence, with the company acknowledging that a large portion of the 3,000 Russian-bought ads specifically targeted election swing states like Wisconsin and Michigan. Although Facebook has since added some small features to help hamper the impact of fake news -- including Snopes fact-checking on stories flagged by users as dubious or potentially fake.

The companies’ executives appeared on Tuesday and Wednesday before members of Congress. The tech giants discussed efforts to combat extremist content and fake news ads from Russia on their platforms, and how Russia interfered in the 2016 presidential election. Tuesday’s hearing was before the Senate Committee on the Judiciary and the Subcommittee on Crime and Terrorism, while Wednesday's hearing was before the Senate Intelligence Committee.

Facebook's egregious role in dispersing paid advertisements and organically shared fake news has been criticized by politicians and voters alike.

In September, Facebook told Congress it discovered $100,000 in ad spending from June 2015 to May 2017, which were linked to the 3,000 ads. Those figures were significantly off. It was reported on Monday that approximately 126 million people in the U.S. may have been exposed to posts, stories and other content created by groups linked to the Kremlin on Facebook. Earlier this month, Facebook said the ads may have only reached 10 million Americans.

Twitter may send Colin Crowell, vice president for global public policy, to speak before the Senate Intelligence Committee. The company previously said it discovered 22 accounts believed to be associated with Russian trolls. Those accounts led Twitter to other 179 related or linked accounts.

As for Google, the company was said to have been investigating the extent to which Kremlin actors used the platform’s websites to spread misinformation to U.S. voters. This month, the search engine company discovered Russia-backed ads on YouTube, Gmail and Google Search. Google reportedly found 18 YouTube channels that were linked to Russian propaganda campaigns.