I do not recall any vents but they were included on the 767 and I was told that the inclusion was due to issues with the L1011 electric doors.
An aside I can recall often 2 BA L1011 rendezvoused at Khartoum in transit (with pax on board) and it was practise to open the doors on the shaded side. No warning barriers or door cable. It used to make me feel stressed as pax and children stood in the open doorway leaning out!