TNT explosions cause the affected blocks to drop items, ex exploded dirt blocks drop the collectable item. This happens in creative mode with difficulty set to peaceful, playing on a server on a local network through port 25565 and no mods on the server or playing machine.
To reproduce this place one or more TNT on any block type then detonate with flint and steel In CREATIVE mode.
Linked issues
duplicates
Comments

Explosions cause the destroyed blocks to drop items in creative mode.
example: if several dirt blocks are destroyed with TNT the dirt blocks will revert to the mini floating blocks that can be collected, This should only happen in survival but it is happening in creative mode.

Aha.
Simply use /gamerule doTileDrops false
if you don't want a single block drop in creative mode.
But duplicate of MC-4681
What exactly is the bug ?