Shares of Digital World Acquisition Corp., which has agreed to merge with Donald Trump's media company, fell 5% in premarket trading Friday after the former U.S. president returned to social media platform X.

On Thursday, Trump marked the return to X, formerly known as Twitter, after more than two-and-a-half years with a post of his mug shot from his booking at Fulton County Jail in Georgia and appeals for donations.

Trump had said he would stick exclusively with his new platform Truth Social, the app developed by his Trump Media & Technology Group (TMTG) startup, after he was banned by Twitter following the Jan. 6, 2021, attack on the U.S. Capitol by his supporters.

He had over 88 million followers on the platform before the ban, while he had 6.39 million followers on Truth Social as of Friday.

The ban was reversed by billionaire Elon Musk in November after he bought Twitter. Trump had said in November he had no interest in returning to Twitter.

Blank-check firm Digital World said in October 2021 it had agreed to merge with TMTG, in a deal that would infuse the Truth Social parent with $1.3 billion in cash.

The deal, however, faced scrutiny for months and Digital World settled fraud charges with the U.S. securities regulator earlier this year that had delayed its closing.

Digital World earlier this month pushed the deadline for the merger by over three months to Dec. 31, in the latest extension.

The company also received a letter from Nasdaq on Thursday stating that it was not in compliance with one of the exchange's listing rule.