Animation seems to be FPS dependent

[Slymeball]

The screenshot animation plays at different speeds with different FPS counts.

20 FPS

Notice how the animation is slower than the other examples. It takes about seven seconds (including the time the photo sits in the corner) to complete its animation.

20fps.mp4

60 FPS

This time, the photo takes less than a second to reach the corner. It takes about two-three seconds to complete this time.

60fps.mp4

Unlimited FPS

This one feels the most accurate to the animation's intentions. I have no idea what causes it to be more normal than the rest.

infFps.mp4

However, it may just be an issue with something else, I'm not quite sure. All I know is that this animation is not consistent.