Unconfirmed from somebody at LHR - Fire is strongly believed to be as a result of galley overheat - failure of coffee heater trip switch which was left on.
Now that is interesting .
In all (old) a/c I flew/still fly there is a master battery switch which is supposed to disable all these, and which you are supposed to use when you park and leave the aircraft. Is the 787 different ? or is it normal to leave power in the galley when long term parked on a modern large aircraft ?