the Airbus design of the A380 is for a inner an outer door for the cockpit crew. EK in their wisdom, changed this to allow passengers to use the toilet/s
PG and the CPD oversaw this redesign with the CPD saying the door was entirely unnecessary. A velvet rope will do instead.
Ironically, having a CC in the cockpit whenever a pilot wants to use the lav means twice as many door openings as otherwise and twice as many opportunities for the security provided by the door to be defeated. The door is opened to admit the CC, then again when the pilot leaves and then twice more again in reverse when he returns.
If they enter/exit at the same time the door is still open for twice as long as normal as they shuffle around each other. Another kneejerk reaction in the rush to be seen to be doing something.