What is a PayPal Coinbase scam?

Could you elaborate on the so-called "PayPal Coinbase scam"? It seems to be a growing concern among cryptocurrency enthusiasts and investors. Are there specific instances where individuals have fallen victim to this scam? What are the typical methods used by scammers to trick unsuspecting users? Is it related to the linking of PayPal and Coinbase accounts, or is it a more elaborate fraud? Understanding the nature of this scam is crucial to protect ourselves from such fraudulent activities. Could you please provide a detailed explanation of how this scam operates and how we can safeguard ourselves against it?