Continuity mistake: In the movie Jack gets the compass from his former captain when he is dying in the battle with Salazar. In the second film we saw that Jack got the compass from Tia Dalma/Calypso.
Plot hole: During the execution scene when Carina is on the gallows with a noose around her neck, the plot depends on Henry being able to get to her before she is dropped through the trap door. However, there is so much slack in the hanging rope that during the chaotic fighting, when Carina is left unattended, she could easily have stepped off the small trap door and onto the solid flooring that is inches away. Instead, she continues standing there, waiting to be rescued.
Continuity mistake: At the end when they board The Black Pearl from the anchor chain, all of the characters are virtually bone dry despite being soaked and submerged by the sea. Henry's sleeves are blowing in the wind.
Revealing mistake: During the bank chase at the beginning the bottom plank is a material skirt which moves forward and backwards revealing in some shots the wheels underneath the bank.