The rear armrest in the center of the rear seatback can be used (no occupant in the center seat) or placed upright.

WARNING
Never put your hands and fingers around the moving parts of the seat and armrest:
Putting your hands and fingers around the moving parts of the seat and armrest is dangerous as they could get injured.
Split Folding
Head RestraintsMazda 6 Owners Manual: Lights-On Reminder
The lights-on reminder is operable when the time setting*1 of the auto headlight
off function is off.
If lights are on and the ignition is switched to ACC or off, a continuous beep
sound will be heard when the driver's door is opened.
*1 If the light switch is left on, the auto headlight off f ...
Mazda 6 Owners Manual: Driving on Uneven Road
Your vehicle's suspension and underbody can be damaged if driven on rough/uneven
roads or over speed bumps at excessive speeds. Use care and reduce speed when traveling
on rough/uneven roads or over speed bumps.
Use care not to damage the vehicle's underbody, bumpers or muffler(s) when driving ...