This UberASM disables the Mushroom/FireFlower/Feather powerup animations and the hurt powerdown animation. You can also disable just one of the two if you want using the defines in the asm file.
Requested by MoghedienNinek.
Works as advertised, accepted. Note that unlike the patch version, the player disappears for one frame when collecting a feather. This (barely visible) effect is purely visual, the game doesn't pause for that frame or anything.
Tested with Asar 1.81, Lunar Magic 3.31, SA-1 1.40, Snes9x 1.59.2, UberASM Tool 1.4.