Can Anyone Shed A Clue As To What This Plug Is? (mistar2)

Wed, 16 Jan 2019 15:06:42 GMT

Down in the drivers foot well, above the door harness connections I saw this loose plug flapping around. Anyone know what it "should" be plugged into.
Everything electrical is working.
Is it a spare connection ?

Car is ADM SW20 1990 G Ltd manual.