The receive() function does not differentiate the source of the incoming ETH. Whether the ETH is sent as intended protocol rewards, or mistakenly sent by an external user, it is processed in the same manner. 
Accidental Deposits: Users who mistakenly send ETH to the contract address will have their funds automatically processed as rewards, with a portion deducted as fees. Since Ethereum transactions are irreversible, once the ETH is sent and processed, recovering it would depend entirely on the actions of the contract administrators, assuming they can identify the transaction as a mistake and choose to return the funds.
Unintended Fee Deductions: In cases of accidental ETH sends, not only is the ETH handled as rewards, but a fee is also deducted and sent to the fee address, further complicating the situation for the unintended sender.
https://github.com/code-423n4/2024-04-renzo/blob/519e518f2d8dec9acf6482b84a181e403070d22d/contracts/Deposits/DepositQueue.sol#L163-L183
