If you spam jump very quickly you can gain great height, and skip levels six, eight, and eleven. Doing the glitch in level 6 lets us grab the pill earlier than intended.

Doing the glitch in level 8, right at the beginning, lets us walk on top of the screen to the end.

Doing the glitch in level 11, on the middle pillar, lets us walk on top of the screen. (Is faster for sure, but is a run killer)

I've found more success with this glitch by using it at the beginning of a level. Namely resetting on level 6 to get the pill seems to be more consistent than the rest.

The faster you perform the glitch the more height is gained (With a cap of course). It is very difficult to perform consistently. May be easier on mobile, which it does work on. (Mobile makes the glitch easier, but slightly different to perform.)

Can't get it to work on the Havana website HTML version. (This is probably because of the HTML version being optimized more than the other websites)

Fun fact: You can get onto the character art at the end of the game with this trick