BTC OG Jameson Lopp and collaborators proposed BIP-361 on April 15, and this one’s pretty interesting—it’s likely to spark major controversy in the BTC community: BIP-361 suggests freezing quantum-vulnerable old Bitcoin addresses (including Satoshi’s 1 million BTC) before the threat of quantum computers arrives, forcing users to migrate their coins to quantum-secure addresses. Otherwise, these coins will no longer be spendable (essentially 'frozen'). After the proposal is activated, sending new coins to old addresses would be prohibited for about 3 years; after 5 years, old signatures would become invalid, and unmigrated coins would be frozen. This is bound to trigger strong opposition from some veteran BTC players, who will argue that it undermines the core principles of 'seizure resistance' and 'trustlessness.' For now, it’s still in the discussion phase on GitHub, hasn’t been implemented, and isn’t a rule passed by the Bitcoin core protocol.