okay, level 21 is definitely the end for me. the controls (maybe lag related or not) are too unresponsive for me to perform these many jumps one after another without falling down.
tip for anyone stuck in the level a while ago wher you need to go up the right to get 2 balls, then the left to get another 2 balls and then from the down down to the portal:
just jumping up doesnt give you enough high, say you wanna climb the right side up, then you actually need to do a moving jump instead of a jump from a standstill.
so go all the way to the right wall and move slightly to the left while jumping. this jumps peak is slightly higher than if you stood there and jumped straight up.