Ignoring that cable is not properly double insulated twin and earth.
And cannot see if a spur off a spur.
And single insulated cables should not be outside the back box.
And Right Back box not sunk into wall so will protrude through plaster further than Left back box.
And earth is not also attached to back box terminal.
It appears that The wires are not passing though a hole in the left hand back box.
They are in-front of the left back box - ready to be chopped off when plaster board is fitted.
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