Scrooge acquires Protect-o-Glass, a special glass from Gyro that makes the Money Bin invulnerable to attack, which puts Gizmoduck out of a job. Nothing, not even Magica's most powerful spells can break through. That is, until Scrooge encounters the Yeeker, a bird that can shatter the glass with an ear-piercing shriek.
Scrooge's nightmare at the beginning of this episode appears to be inspired by the opening of the Italian-produced Uncle Scrooge comic story "The Money Ocean" by Marco Rota, first published in Almanacco Topolino #215 in 1974.
Differences from the original comic
Besides the obvious "Donald's not in this version."
The original story opened with Scrooge having already gotten his unbreakable glasses (which he mentions were developed by his scientists rather than Gyro) and showing them off to Donald.
The unbreakable glass was not called Protect-o-Glass in the comic.
In the comic, Scrooge didn't get the idea to coat the Money Bin in the unbreakable glass until after seeing one of the Beagle Boys' failed attempts to break his safe open.
The comic did not have the unbreakable glass being used to coat all of Duckburg.
The comic had a running gag in which a police officer had to order the Beagle Boys, and later Magica, to leave the Money Bin because an old lady was complaining about the noise they were making.
In the comic, Magica was actually able to get the Yeeker to break open the Money Bin's safe. However, because it took her hours to actually get the Yeeker to cooperate, Scrooge and the nephews made it back just as she was making off with the Dime, and when she tries to zap them with her stun ray again, she found that its battery had died, and Scrooge managed to snag the Dime back in the process.
The Yeekers were never shown to lay any eggs in the comic.