Has Monero ever been traced?

Have there been any instances where Monero transactions have been successfully traced back to their original senders or receivers? As a privacy-focused cryptocurrency, Monero is known for its ability to obscure transaction details, but is this level of anonymity truly unbreakable? Have there been advancements in blockchain analysis or other investigative techniques that have challenged Monero's claims of privacy? Are there any known cases where law enforcement agencies or other authorities have been able to uncover the identities of Monero users?