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: Manual Transaxle Shift Pattern
The shift pattern of the transaxle is conventional, as shown.
Depress the clutch pedal all the way down while shifting; then release it slowly.
Your vehicle is equipped with a device to prevent shifting to R (reverse) by mistake. Push the shift lever downward and shift to R.
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Mazda 6 Owners Manual: Cooling system service warnings
COOLING SYSTEM SERVICE WARNINGS
Warning
Never remove the radiator cap or loosen the radiator drain plug
while the engine is running, or when the engine and radiator are hot.
Scalding coolant and steam may shoot out and cause serious injury. It may
also damage the engine and cooling sys ...