[BACKPORT REQUEST]: v3.0.x for 1.21.4

[Oltrex]

Before creating a request, please make sure you have checked the following:

• Similar request had not already been reported before in the issue tracker.

What has to be improved/added?

1.21.4 supports most popular mods and its not that old, a lot of people are probably gonna stay on it for a long time, it would be amazing to have DH support for it since it barely missed it arriving for 1.12.5 instead.

[kerudion]

Hi! I'm currently busy with another project and can't do that. When I'll be free, I'll first fix the most critical and annoying bugs found in 3.0.0, and then backport it to most likely all versions.