See that L-shaped metal bracket sticking out to the left of the current main breaker? It looks like if the breaker were in the left position instead, that bracket would engage the notch in the end of the breaker to hold it down.
That breaker should be moved to the designated position, and it looks like you have slack in the wire to do so. The reason code requires some means of holding down a backfed main breaker is so that there won't be a breaker with energized bus clips flopping around if it is accidentally or intentionally removed from the bus.
That breaker should be moved to the designated position, and it looks like you have slack in the wire to do so. The reason code requires some means of holding down a backfed main breaker is so that there won't be a breaker with energized bus clips flopping around if it is accidentally or intentionally removed from the bus.
