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: Driver-side air bag module removal/installation
Warning
Handling the air bag module improperly can accidentally deploy the
air bag module, which may seriously injure you. Read AIR BAG SYSTEM SERVICE
WARNINGS before handling the air bag module. (See SERVICE WARNINGS.)
Due to the adoption of 2-step deployment control in both the
driv ...
Mazda 6 Owners Manual: Tire Inflation Pressure
WARNING
Always inflate the tires to the correct pressure: Overinflation or
underinflation of tires is dangerous. Adverse handling or unexpected tire failure
could result in a serious accident.
Use only a Mazda-genuine tire valve cap: Use of a non-genuine part
is dangerous as the correct tire ...