A side note re: sliderafts. The B777 operator I fly for has silver colored sliderafts. It's the CANOPY which gives an orange/red color. This is separate to the slideraft and is to be installed by the crew for use on water (for obvious reasons) Anyone's know if MAS are different?
IIRC the only rafts I've ever used which themselves were yellow were those carried on B738 or supplemental carried in cabin on paxseats as part of overwater operations for aircraft normally limited to closer to land...
ETA: Evenrude's pic confirms same
As you can see they are pretty stinking big when inflated, certainly larger than the "door"-like object spotted earlier (which to me looked more like the plastic lav surround than a 777 door)