Continuity mistake: Cigarettes and food items changing size/shape between shots.
Common movie and TV mistakes
This is a list of mistakes, things done wrong, etc. that happen so frequently onscreen we barely notice any more. 'Movie logic', stupid behaviours, and everything related.
Continuity mistake: Countdown timers that bear no relation to reality.
Continuity mistake: In episodic television shows, the heroes can be shot, stabbed, have broken bones, etc., but these vicious scars and injuries are never carried forward into the following episodes - the heroes are unscathed.