FallingBlocks
Lets you enable/disable the gravity of (most) blocks.
Simply add them in the form of modname:block_name inside config/fallingblocks/config.json
Enabling blacklist gives gravity to all blocks excluding the ones inside the blacklist itself.
If you enable blacklist, do not remove blocks like stone, dirt or grass. It can cause massive performance issues.
Credits:
Code & icon: DH#9367 (discord)