Auto Ladder
Places a ladder where you land to cancel fall damage.
A ladder only catches you if a tick starts with your feet inside it, so while you're falling it works out where your feet will be at the last tick before you hit the ground and puts the ladder there. At speed that's a block or more above the ground. It hangs the ladder on a wall at that height, and when there isn't one, it builds a short pillar beside you to hang it on, one block a tick, or all at once when you'd land first. Your camera doesn't move while it turns to place, and your slot goes back once you're caught.
It needs ladders and plain full blocks in your hotbar, and does nothing in creative, while flying, or while Block In is working.
Min fall distance
Falls shorter than this, counting what's left to the ground, are left alone. Jump Boost raises it by a block per level.
Only while holding ladder
Only start when you're already holding ladders.