There was a thread yesterday, which has been deleted, that suggested that a particular play on the final drive in the Bombers-Riders game was obviously offside. In that thread, I promised to post screen shots to show that the receiver was still onside at the snap of the ball. Here they are.
The ball has not yet been snapped in this shot. The line of scrimmage is right on the 35 yard line.
In this image, you can see the ball has started moving back. All visible Riders players are onside at this point. The twelfth player must be the near-side receiver on the line. No guarantee that he’s onside, but given that he’s not supposed to be in motion, I would expect this to be easily picked up by the linesman.