Player blink animation in third person plays too slow when the paper doll is rendered

Summary:

The speed of the eye blink animation with shift is different from the speed of the animation without the shift. This also occurs when sprinting.

How to Reproduce:

1. Make a skin with eyes from the skin editor.
2. Watch the blinking animation with and without shift.

Observed Results:

Animation speed differs with and without shift.

Expected Results:

The animation speed does not differ.

Video:

(video without slowdown)

Minecraft 2021-02-18 21-19-36.mp4

Minecraft 2021-02-18 21-17-53.mp4