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: Air bleeding
1. Inspect the fluid level. (See POWER STEERING FLUID INSPECTION.)
2. Jack up the front of the vehicle and support it on safety stands.
3. Turn the steering wheel fully to the left and right several times with the
engine not running.
4. Reinspect the fluid level.
If it has dropped, add flui ...
Mazda 6 Owners Manual: Rear seat disassembly/assembly
4SD
1. Disassemble in the order indicated in the table.
2. Assemble in the reverse order of disassembly.
5HB
1. Disassemble in the order indicated in the table.
2. Assemble in the reverse order of disassembly.
...