Unlike other upgrades, such as Pectra, this change would not require a hard fork. It can be adjusted by Validators through node configuration while proposing blocks.
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Ethereum Validators Hint at Doubling Gas Limit to 60 Million Units
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Increasing Ethereum's block gas limit from 36 million to 60 million units can be implemented without a hard fork, as validators are able to apply the change by modifying their node configurations during block proposal.
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