I found your impressive website and thought I would ask a question I have been thinking on for a while:
Should the game be restarted when a drop-goal is kicked after time has expired? No seems to be the answer in practice but reading law 5.7 I don't think that is an obvious interpretation. 5.7(e) says that
"If time expires and the ball is not dead, or an awarded scrum or lineout has not been completed, the referee allows play to continue until the next time that the ball becomes dead. The ball becomes dead when the referee would have awarded a scrum, lineout, an option to the non-infringing team, drop out or after a conversion or successful penalty kick at goal. If a scrum has to be reset, the scrum has not been completed. If time expires and a mark, free kick or penalty kick is then awarded, the referee allows play to continue."
My problem is that a drop goal is not a conversion or a penalty kick and the referee would not award a scrum, lineout, option or drop-out. And the specific mention of one type of goal but not drop-goals suggests that drop goals were specifically excluded.
Is there something in the laws that I am missing?
If the ball becomes dead that is the end of the game, otherwise play on. So in your scenario if the drop goal is short and lands in the field of play, then we just play on. If the drop goal goes long, or is touched down in the in-goal area, then we finish the game because you quoted the law yourself:
The ball becomes dead when the referee would have awarded a...drop out...If the drop goal goes long or is touched down we would restart with a drop-out, so the ball has become dead at that point; game over.
The Rugby Ref