Check out this fan-captured clip from Disney California Adventure Park -- Just before a battle scene, the unidentified actor jokes about his late arrival ... saying, "Cinderpool was late because he had to read every single page in the terms and conditions when he signed up for Disney+."

The Wolverine actor chimes in with, "I don't get it" -- Deadpool fires back, "They do." And sure enough, the whole audience gets it, bursting out laughing.

But, that joke’s got a dark, tone-deaf twist ... considering a man recently sued Disney after his wife died from a food allergy reaction at a Disney World Irish pub in Florida last year.

As we know from court docs obtained by TMZ earlier this month ... Disney had one heck of a defense: The guy's Disney+ subscription supposedly stops him from taking them to court, because it includes a clause saying any disputes have to go through arbitration, not the courts. Arbitration is private, preventing any potentially bad PR from going public.

Disney had asked for the wrongful death lawsuit to be kicked out of court, because the plaintiff, Jeffrey Piccolo, agreed to arbitrate all disputes against Disney when he signed up, back in 2019, for a one-month trial of its streaming service. However -- last week, Disney announced the company would no longer seek to dismiss the lawsuit.