Informal announced CometBFT today, a new consensus engine for Cosmos chains. To avoid confusion, this is a direct fork of Tendermint (more specifically v0.34) and will be swapped in for Tendermint on both new and existing chains. As of now you can think of it as Tendermint under a new name.
Why the fork? If you are unaware, Tendermint is being archived because of a decision by AiB, the original developers who maintain the trademark and removed Informal from the repo a few weeks ago. Informal will continue development under this new name and push new features like ABCI++.