When I tried binding the cap key to sneak it didn't work at all. I had it before already assignes to it, but in 17w43a nothing happened when I pressed the button. In Minecraft:Jave Edition 1.12.2 and below this bug wouldn't appear to me.
Environment
MacOS 10.10.5
Minecraft: Snapshot 17w43a
Please do not mark unreleased versions as affected.
You don't have access to them yet.