That is random, but this seems to be the place for random questions, so why not?
According to wikipedia, a popover is 'a light, hollow roll made from an egg batter similar to that used in making Yorkshire pudding. The name "popover" comes from the fact that the batter swells or "pops" over the top of the muffin tin while baking. They can also be baked in individual custard cups.'
But I didn't really know that. I just knew that the quotes came from a movie I loved growing up,
The Muppet Frog Prince (loosely of course since the the frog in the movie was a he). Well, anyway, the witch in the movie keeps sticking popovers in the frog's mouth so he can't tell the king about her evil treachery and then later she tells the king that 'we can't let the frog go hopping around the castle' and he agrees, because the frog ate all the popovers.
So basically in context it means 'Shut up, Frog!' which applies to me often on the forum, so I put it up... even if I am probably the only one that would understand it.