Around 00:27:39, driver's window is open. In the next shot, the window is closed.
At 31:10, when Thierry is chasing his son and gets stuck, the left rear-view mirror is covered with mud. At 32:40, when he resumes the chase, the mirror is clean.
Around 01:01:50, Hélène is talking to François through a two-way mirror. Around 01:01:54, she turns her look to her left, to Albert. Later, around 01:02:18, when she get up, she's looking at François again. She can't see them through a mirror like this.