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: System wiring diagram
ABS (ABS/TCS)
DSC
FOREWORD
Before performing the steps in Symptom Troubleshooting, perform the
On-board Diagnostic Inspection. To check the DTC, follow the DTC Inspection
steps.
...
Mazda 6 Owners Manual: Gate operator/Canadian Programming
Canadian radio-frequency laws require transmitter signals to “time-out” (or quit)
after several seconds of transmission — which may not be long enough for HomeLink
to pick up the signal during programming. Similar to this Canadian law, some U.S.
gate operators are designed to “time-out ...