Apparently there is a new danger in the business of flying. People are increasingly reporting that their laptop screens are being cracked by the decision of the person sitting ahead of them suddenly to dump the seat back into the lazyboy position.
This used to be infuriating enough, but imagine having a seventeen hour flight with some snoring stranger in your lap -and a smashed laptop aaarrgghh!

Today’s invention is a cardboard tube which fits over the end of all armrests and obscures the ‘reverse’ button. To release it, you have to slide the tube off. This action takes a couple of extra seconds and exposes a sign on the other end of the armrest, which attracts the attention of the person behind.
The sign would say “look out, seat back about to descend!”