The goof item below may give away important plot points.
Anthony Geiger, Sloane's replacement as head of SD-6, discovers a suspect email. He has the security chief Calvin McCullough play back the keystroke log that was recorded as Sloane typed the email. As we see the playback, we see that Sloane typed a section revealing that Jack and Sydney are double agents, then erased it. However, this section of the email is clearly already visible as McCullough sits down at the desk.