Platform allows the player to be "planted" to the ground slightly so that the feet tile is Y+1 than it should be

[curioustorvald]

How to reproduce:

1. On the above block placement, stand slightly (a pixel or two) left to the platform, then hold down and right at the same time
2. If all things worked well, your position will be Y+0.9 more than it should be (for the above screenshot, Ypos should be 5152.0 rather than 5152.9037)
3. You'll know it worked because now you're walking as if you're on a block of ice because the game's reading the friction value of the air tile as the feet tile position is Y+1 than it should be