Continuity mistake: When Toad General calls for the council's attention and announces that Bowser found the Super Star, note his shirt buttons. Then, when he says that the Kongs will never agree because their mad king doesn't make alliances, Toad General's shirt is backwards, his buttons are on the opposite side. (00:24:55 - 00:25:35)
Continuity mistake: When a guard aims to hit Hespera and Kalypso with his baton, they freeze him. However, an instant cut later from the opposite angle, his position is totally different.
Continuity mistake: When Letty places the necklace on Dom, the actual cross is almost touching the neckline of his top. When the shot changes, the cross is much lower down the chest. (00:15:05)
Continuity mistake: When the villains are following Indy through the caves, the old wooden bridge completely breaks and falls apart. However, when they make their escape across the same bridge, it's intact with only a couple of wooden slats broken.
Revealing mistake: While inside the tunnel in Rome, before the yellow Fiat makes a U-turn multiple skid marks from previous takes are visible. Though one might pressume that the marks were already there, they are at the same spot and have the same pattern as the skid marks that the cars make seconds later.
Continuity mistake: When the movie begins, the way the barista holds his notepad changes between shots. (00:01:07)