The bug
When the player is standing in a 1.5 blocks tall space and releases the sneak key (usually Shift), it can move at normal speed and even sprint.
To reproduce
Sneak below a half slab
Release the sneak key
Start walking or sprinting
❌ You move at normal walking / sprinting speed
Linked issues
relates to 3
Attachments
Comments 3
Most likely working as intended, since any means of existing in a space of such a height (e.g. by using an ender pearl) will put you into the sneaking position anyway.
Yep, I can reproduce this in 19w14a.