Minecraft version(s)

1.20.1

Minecraft version details

No response

Mod loader

Fabric

Mod loader version

0.16.9

Fabric API version

fabric-api-0.92.2+1.20.1

In what kind of world or server did the problem occur?

Singleplayer and Multiplayer.

What went wrong? (Crash logs don't go here)

With Pehkui and Valkyrien Skies, a curious physics bug emerges.

sliding against a wall while holding a directional key and space causes the player to accelerate upwards.

This might actually be a bug in Valkyrien.

Recorded a video for you. Please excuse the compression, I had to take it down to 10MB. Also i forgot to turn Minecraft's music down.

EDIT: GH refuses to display this file no matter how many times i reuplaod it. https://youtu.be/HIQsreidUMI

and here's a pack export which reproduces the issue:

Pehkui & Valk conflic test 1.20.1.zip

Full list of installed mods and their version numbers

fabric-api-0.92.2+1.20.1
Pehkui-3.8.3+1.14.4-1.21
valkyrienskies-120-2.3.0-beta.5

Did the problem cause the game to crash?

No.

Full crash report contents (if you experienced a crash)

Also reported as ValkyrienSkies/Valkyrien-Skies-2#1043. Y'all can figure out which mod's problem it is between yourselves :)