[Coinbase Releases Bitcoin Post-Quantum Upgrade Proposal: Calls for Multi-Year Migration Planning in Advance] Coinbase has published a technical discussion article on Bitcoin's post-quantum security (Post-Quantum Readiness), stating that Bitcoin must proactively address potential cryptographic risks posed by quantum computing in the future and suggesting that the community initiate related migration preparations as early as possible. Coinbase believes that Bitcoin's post-quantum upgrade involves not only selecting new quantum-resistant signature algorithms but also comprehensively considering factors such as block space limitations, full node verification capabilities, institutional custody requirements, compatibility with standard wallets, and solutions for handling funds that cannot be migrated. Bitcoin should consider introducing output structures that support quantum-resistant signatures and explore hybrid solutions, such as enabling the same funds to have both traditional ECDSA/Schnorr signatures and quantum-resistant signature authorization paths simultaneously, to achieve a smooth transition.