Inconsistencies
For the record, I did enjoy this movie, although I don't think it was quite up to the level of its predecessors in most ways. But I felt like the movie had enough inconsistencies that it almost didn't even feel canon to the series to me. For instance, it's already been discussed how Will is inexplicably turning into Davy Jones with no explanation whatsoever, implying that simply being captain of the Dutchman will turn him into Jones. But here's another:
The compass. Jack giving away the compass supposedly releases Salazar from his imprisonment. But Jack has already given away the compass several times, to Beckett and to Will. Why would this action not have released Salazar then, but giving it away now did?
Also, in Dead Man's Chest, Tia Dalma said that Jack bartered the compass from her ("The compass you bartered from me, it cannot lead you to this?", in reference to the chest of Davy Jones). But here in this movie we see that Jack received the compass from a fellow pirate in his youth. I supposed it could be theorized that he lost the compass somehow and had to get it back from Tia Dalma (though that's a bit of a stretch, and if that were the case it would make Tia Dalma's wording a bit odd, since it was his compass in the first place). But to me it just feels poorly thought-out.
What do others think? Perhaps i'm griping about petty things, but i'm a stickler for consistency and these just feel like pretty big holes to me. I generally felt, even besides consistency issues, that the writing in this movie was subpar compared to the other POTC films.