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Proposals allow accounts with the PROPOSAL permission to propose an alteration to the network. A proposal contains a batch of normal transactions that will be executed with elevated permissions once ratified by a ballot (consisting of accounts also having PROPOSAL permission). This ratification allows a network with no direct human superusers to upgrade the contracts on that network. It is how we intend to upgrade code on the Agreements Network.
GovTx
GovTx is a transaction type that is often behind a proposal-wall with the ability to arbitrarily update an on-chain account (therefore contract in the Ethereum world view). This transaction can break the invariants of conservation of token and code immutability. As such it requires the ROOT permission. Generally expected use is within the context of a proposal; however, administrative account or contact use can be granted.
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