where do I go to play v1.3 unblocked of slope for it to count on the leaderboard? I have a website to play it on but it isn't the same as others

I see all these people going through the blue dots on level 7. I know that its a glitch and I know why it happens but whenever I go into level 7 and try to get into the exact spot or just go left and right without moving up or down at all I still die, I don't know if its because of my window size or version of the game, if anyone has an idea why this is happening please tell me, I need to speedrun level 7 faster.