Bonsai Trees version:
bonsaitrees-1.1.3-b156

Forge version:
forge-14.23.5.2847

I am not using Optifine:
I am using it, but the bug isn't visual.

Link to Crashlog: here
N/A

Screenshot (if possible): here
I can post one but it just says "You do not have the permission to use this command."

Description of the problem including expected versus actual behavior:
When trying to run /bonsaitrees generateMissingShapes yes I get the above error. I've tried on two separate flatworld worlds, cheats enabled. Not sure what the issue is.

Steps to reproduce:

1. Create Flatworld world
2. Look at the ground
3. Run //bonsaitrees generateMissingShapes yes command

I know this issue has been opened before but I didn't see a resolution. Any updates on this? Am I being dumb with something?

I had the same problem, it worked once I set the gamemode to Creative.

I figured it out. I was doing it wrong.