NoBlackSky plugin has been updated to
2.4 and it is now compatible from 1.8 to the latest
1.18 spigot version.
The bug "
The method getWorld is not supported for temporary players" has been fixed from server 1.16+.
If you want to know why this bug won't be fixed prior to 1.16, read the issue tracker on GitHub at the following link:
getWorld() is not supported error.