My game is crashing when there are more than 15 block types used in a normal sized block area.

crash-2021-06-22_16.46.22-client.txt

For any bug reports please provide the following details as well,

• MC Version: 1.16.5
• C&B Version: 0.3.4
• Do You have Optifine: Yes, it also crashes without Optifine

Update to the newest beta.
It won't fix already broken blocks, but it will prevent it.