Jaytip Tony is correct
Endgame was within 1% of overtaking but slowing so they pushed out ‘extras’ to get the die hard fans to make sure it surpassed which in all probability it would have anyway.
The Guardian
Still, it did the job. The Endgame re-release was a transparently commercial manoeuvre, cynically willed into existence because the original run couldn’t quite squeeze past Avatar to become the highest-grossing film of all time. Chuck in a handful of scraps – without even integrating them into the film – in the name of fan service, and bingo: Endgame just about nosed it.