There are too many members of the Kingsguard: they are supposed to be seven at most. Jaime is in Dorne; Cersei sent Meryn Trant to escort Mace Tyrell to Braavos; Myrcella was sent away to Dorne with Arys Oakheart. Yet when Tommen tries to visit the High Sparrow, there are five Kingsguard members with him - plus Jaime, Meryn, and Arys make eight, not seven.
At the end of the last fight, Grey Worm lies down with his head close to the corpse of one of the Sons of the Harpy. Then the camera changes to aerial view, and the corpse is gone.
The sailboat's point of sail changes in the shots between Jorah and Tyrion. When the camera is on Jorah, the sail is on a port tack; when it's on Tyrion, the sail is on a starboard tack.
When Bronn is talking with Jaime on board the ship, he cleans his knife in a casual, but firm manner. While doing so, he runs his hand along the edge of the blade. If the knife was real, Bronn'd have most likely sliced his hand open.
The on-screen subtitles misspell the name "Mazin" as "Mayzen."