Registry remapping fails with NullPointerException when using Wood API in multiplayer (1.21.1)

[FarestR06]

I'm working on a mod (1.21.1), but I had a weird issue. Whenever I tried to join a multiplayer server with my mod installed, the game would crash. Just before the crash, an error screen saying "Registry remapping failed: null" would show up for a split second.
After a bit of debugging, I was able to narrow down the cause to an issue with the Wood API. I managed to fix the issue by simply removing the signs and boats. And I'm now here in the issues, filing a bug report. As I already mentioned, I'm playing on 1.21.1, so I'm not sure if the issue has already been fixed.

Oh, and here's the log file.
2024-12-27-4.log

[gniftygnome]

This sounds like maybe some missing initialization. Perhaps the client-side boat init?

f.e.: https://github.com/TerraformersMC/Traverse/blob/1.21/client/src/main/java/com/terraformersmc/traverse/TraverseClient.java#L18