In creative mode if your boat falls into lava at high speeds then the player is unable to place anything or even break blocks instantly. I have been able to reproduce this bug in the overworld and nether. This does not happen if the boat just falls into the lava at slow speeds. When I found this out, I was on blue ice going really fast, then fell off into lava, where I then was unable to place blocks, place a boat, or even break blocks instantly. Sometimes I am able to break the blocks but not always, and this is all in creative mode. My player hand also disappears from the first person view.
Environment
My computer runs Windows 10 and this happen on the Java edition of Minecraft Pre-release 2 in a single player creative mode world.
Duplicate of MC-186085.