At the art gallery, when Philippe asked Driss to give him an M&M, Driss reached out and gave him the green one. By the next shot, the candy given to Philippe's mouth is yellow.
The size of Philippe's tracheotomy scar changes noticeably from one occasion to the next.
When Driss comes to get his document, you can see a no-parking sign with the words "jour et nuit" outside the mansion. Later, when Driss beats the neighbor, the sign is different.
(1:15) Philippe and Driss are talking on the phone and for Philippe it's daylight while for Driss it's nighttime. They are in the same city
There are two different Maseratis used in the film. In the opening scene, there is a different car used for the fast part of the car chase - notably a Quattroporte GTS 4.2 that can be identified by a chrome mesh grill and four exhausts. At the part where they are stopped by the police, a different front grill can be seen with vertical segments, and when they drive off two large exhausts are visible. It is one of the 4.7 versions of the Quatroporte. The 4.7 version of the car is again shown when later Driss gets in the car for the first time.
When Driss is first learning how to care for Philippe, it is shown that Philippe can't sit upright by himself. However, the strap that is used to hold Philippe upright in his wheelchair sits so low on his waist that it couldn't possibly support his torso. However, most chairs for quadriplegics have cushions placed on the back in such a way that they cannot move sideways.
While tailors are measuring Driss for a new suit, Philippe's feet or legs move briefly up and down even though he is quadriplegic.
When the police car first appears behind Driss, you can hear a short burst of the siren, which is clearly an American-inspired tone (also used in UK etc.) When the pursuit begins, the police car has the recognizable and correct French siren tone.
When paragliding, Driss can be seen holding a stick in his right hand that the camera, for close up shots, is attached to.
When paragliding, the shadow of a cameraman is briefly visible over Driss.
Driving north to Dunkirk at the end would have taken place in the morning after their night adventure. The sun would have been rising in the east, instead of setting in the west. So, either the time of day is wrong, or the direction they are driving.
In the beginning, where the police escort Driss and Philippe, the police car in the back has a broken tail light.