In the outdoor market scene, the amount of food laid out on the tables varies from shot to shot. The reason is that the extras were famished from years of wartime food rationing, and stole food whenever they were not closely watched.
The positions of Avril and Lacenaire in the Turkish baths changes between the shot of their entry and the closer shot.
During the shots from the audience POV in the theater where the orchestra conductor is visible, he is clearly wearing contemporary glasses (1940s) even though the film is set in the 19th century.