The PR [R4R] Separate Processing and State Verification on BSC introduced two roles: Fast Node and Verify Node.

The Fast Node, which processes blocks using only state snapshots, is a useful feature in my opinion.

However, I'm unsure whether the Verify Node is still being used. About 7 months ago, during an upstream merge, I unintentionally introduced a bug here:
https://github.com/bnb-chain/bsc/blob/master/core/state/stateupdate.go#L181, found by @flywukong

This change effectively broke the Verify Node functionality, yet no one has reported an issue since then, which makes me question whether it's still in use.

There is a considerable amount of code related to Verify Node. If no one is using it anymore, perhaps it would be better to remove this code entirely. Otherwise, we’ll need to keep maintaining or fixing it whenever we do upstream merges.