Describe the bug
See title. Pam's seems to replace the entire loot list, instead of adding to it (Much like occultism did in the first public release)

Expected behavior
Datura seeds should drop even with Pam's installed.

Solution
Contact Pam if they are interested in using the same solution that was contributed to Occultism.

So I don't have Pam's installed but also am not getting seeds... perhaps a conflict with a different mod?

I'm not seeing the Occultism seed drops from grass, but I am seeing seed drops from multiple other mods, so I don't think it is caused by some other mod replacing the loot table entirely...

So I just tested with only Occultism, and still got no datura seed drops.

I then took a look into how the various mods in my pack are adding seed drops to grass:

• A couple are using Global Loot Modifiers.
• One is just hooking the onGrassBroken event directly.
• I'm not using Pam's, but I looked anyway, and the 1.15 version appears to be using the same approach you are. I haven't checked to see if Pam's drops work.

Should be fixed with b23cb0b for all future versions (for MC 1.16.4)