Aug 9 (Reuters) - Cinema operator AMC Entertainment (AMC.N) beat second-quarter revenue estimates on Monday, lifted by the return of moviegoers to its theaters after a year of closures and restrictions, sending its shares up 4% in extended trading. "F9: The Fast Saga" - the latest installment of the "Fast and Furious" series - and "Godzilla vs Kong" gave AMC much-needed relief from the blows it has taken from the pandemic over the past year. Chief Executive Officer Adam Aron said U.S. ticket revenue in the third quarter was on track to reach 45% of the same quarter in 2019. "That trend line is pointing up. We certainly have a way to go but the progress is clear," Aron said on a post-earnings call. The company also announced a deal with Warner Brothers for an exclusive theatrical window of 45 days prior to home release for all Warner Brother films in 2022. "The decision to go back to 45 days is great," said Wedbush analyst Michael Pachter. He added that AMC will have the technology in place to receive payment for movie tickets and concessions in bitcoin by the end of the year. read more Responding to pre-submitted questions from individual investors, Aron entertained selling merchandise from theaters, and he said AMC would discuss potential partnerships with GameStop(GME.N). Revenue at the company, one of the "meme stocks" at the center of a boom in small-time investing this year, rose 19% to $444.7 million in the quarter ended June 30. Analysts on average had expected $382.1 million, according to Refinitiv IBES data. AMC raised another $1.25 billion of new equity capital in the quarter, taking AMC"s quarter-ending liquidity to more than $2 billion. Excluding items, the company posts a loss of 71 cents per share, much smaller than analysts" expectation of 91 cents.