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: Ignition switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the ignition switch connectors.
4. Inspect for continuity between the ignition switch terminals using an
ohmmeter.
If not as specified, replace the ignition switch.
...
Mazda 6 Owners Manual: Rear outer handle removal/installation
1. Remove the rear door glass.
2. Remove the rear door unit.
3. Remove the rear door latch.
4. Remove the bolts.
5. Detach the rear outer handle and rear door latch rod.
6. With the rear side of the rear outer handle fixed and the outer handle
lever pulled out (1), remove the rear side of t ...