The spine-unity runtime is not officially supported for Unity 6 as it is still in beta. However, some users have reported that it works for general use, though it is not recommended for production projects with fixed release dates. There have been some bug fixes related to Unity 6 in the Spine 4.2 branch, but no new Unity 6 bug fixes will be published on the 4.1 branch. Unfortunately, there is no specific release date for when the spine-unity runtime will officially support Unity 6. If you want to experiment with Unity 6, you can try using the latest spine-unity runtime, but be aware of potential issues.