Underneath a picture of Zuckerberg sitting with him in the White House, Trump complimented the Facebook founder for coming to see him, how nice he and his wife were, and railed against his “PLOT AGAINST THE PRESIDENT,” in 2020. Zuckerberg was a proponent of installing locked ballot drop boxes at various locations to make it easier for absentee voters to drop off ballots when restricted by COVID-19 rules. The drop boxes and other mail-in voting mechanisms that were used in 2020 are at the center of Trump’s baseless accusations that he lost the contest to President Joe Biden as a result of massive voter fraud.

“He told me there was nobody like Trump on Facebook,” Trump wrote, according to Politico. “But at the same time, and for whatever reason, steered it against me. We are watching him closely, and if he does anything illegal this time he will spend the rest of his life in prison — as will others who cheat in the 2024 Presidential Election.”

Threats to throw the book at people deemed election fraudsters by Trump, and against Zuckerberg in particular, aren’t new.

Trump lobbed a similar threat at Zuckerberg in a July Truth Social post in which he threatened to pursue “ELECTION FRAUDSTERS at levels never seen before, and they will be sent to prison for long periods of time. We already know who you are. DON’T DO IT! ZUCKERBUCKS, be careful!”

In Save America, set to be released Sept. 3, Trump writes about how Zuckerberg and his wife, Priscilla Chan, donated $420 million to election centers that disproportionately went to Democratic-leaning districts and jurisdictions. Known as Zuckerbucks, the private money was being allocated by a third party called the Center for Tech and Civic Life, which gave them a say on how the election was administered and also allowed them to assist with operations such as curing ballots.

Zuckerberg announced that he has stepped away from CTCL, which is still consulting with election offices. He also said he would not make any campaign donations or endorse any political candidates.

Earlier this week, Zuckerberg wrote in a letter to the House Judiciary Committee saying he regrets bowing to the pressure of the Biden administration to suppress posts and content related to the COVID-19 pandemic, including satirical posts and humor.

“I believe the government pressure was wrong, and I regret that we were not more outspoken about it,” Zuckerberg wrote. “I feel strongly that we should not compromise our content standards due to pressure from any Administration in either direction — and we’re ready to push back if something like this happens again.”

In the hearing, Zuckerberg also mentioned how Meta was instructed to suppress news articles and posts circling about Biden’s son, Hunter Biden, and the contents of his laptop. However, at the time, the FBI suggested that the media coverage was actually a Russian hoax meant to influence the election.

Zuckerberg said it has “since been made clear that the reporting was not Russian disinformation, and in retrospect, we shouldn’t have demoted the story.”