This is an illustration of the F9F Panther seat from the F9F-5 Flight Manual.
Note that the headrest can be tilted forward. (In that illustration, the ejection handle is shown pulled with the face curtain partly extended.)
The ejection handles were actually rope and generally lay against the front of the headrest.
However, when the headrest was tilted forward, the ejection handles lay across the top of it.
The F9F-5s were delivered with this seat.
As were the first Cougars.
The headrest was subsequently changed to be smaller and incorporate a rigid ejection pull handle instead of ropes.
The headrest was also curved from side to side instead of flat, and set higher.
This seat became the production standard for the Cougar and was retrofitted to F9F-5s at overhaul.
The Grumman seats in the F9F-8T two-seat Cougar had yet another headrest.
These were replaced early on by a Martin-Baker seat.
The single-seat Cougars operated by the Navy training command were also retrofitted with the Martin-Baker seat.