This referendum enables two approval voting protocol improvements that are a prerequisite to **scale up the number of Polkadot validators to 500**.  

Once enacted, the validators will start using the new format for approval voting assignments and also approve multiple candidates under a single signature. The impact is the reduction of network bandwidth and CPU usage of the approval voting protocol.

High level tracking issue for scaling the validator set: https://github.com/paritytech/roadmap/issues/26

Relevant node side changes (released Q4 2023): 
- v2 assignment certificates : https://github.com/paritytech/polkadot-sdk/pull/1178
- approval of multiple candidates with single signature: https://github.com/paritytech/polkadot-sdk/pull/1191

Whitelisted by https://collectives.subsquare.io/fellowship/referenda/130

See [`Pallet::dispatch_whitelisted_call_with_preimage`].

- Problem Statement: Enhancing approval voting protocols to accommodate 500 Polkadot validators.
- Significance: Reducing network bandwidth and CPU usage for approval voting.
- Proposed Solution: Implementing new approval voting format and allowing approval of multiple candidates with a single signature.
- Expected Outcomes: Improved scalability and efficiency for Polkadot validators.

#888 Enable approval voting protocol improvements

No Active Proposals