Iron blocks do not make a falling sound.

Old worlds don't say they need to be converted

You can take campfire damage in a block.

The boat's hitbox can glitch, so, you can be stuck in a block, or in a very buggy animation...

When a boat is placed on water, it is placed in the wrong direction the player is looking.

End crystals explode when placed on obsidian or bedrock in the End

Ominous Vaults do not appear in the creative menu and cannot be placed with the "/setblock" command.