The main performance improvement concerns gRPC queries, which are now able to run concurrently on the node ([\#10045](https://github.com/cosmos/cosmos-sdk/pull/10045)). To benefit from this performance boost, make sure to send your gRPC queries to the gRPC server directly (default port `9090`) instead of using the Tendermint RPC [`abci_query` endpoint](https://docs.tendermint.com/master/rpc/#/ABCI/abci_query) (default port `26657`).
- bumps Tendermint to [v0.34.14](https://github.com/tendermint/tendermint/releases/tag/v0.34.14).
- bumps the `gin-gonic/gin` version to 1.7.0 to fix the upstream [security vulnerability](https://github.com/advisories/GHSA-h395-qcrw-5vmq).
- adds a null guard with a user-friendly error message for possible nil `Amount` in tx fee `Coins`.
See the [Cosmos SDK v0.44.3 milestone](https://github.com/cosmos/cosmos-sdk/blob/v0.44.3/CHANGELOG.md) on our issue tracker for the exhaustive list of all changes.