When wearing a leather helmet that has a "pastel" sort of colour such as light pink, if the player looks in certain directions, the colour will completely disappear and just turn white. The exact colour code I used is #FFA6A6
I've tested this in 1.14 up to 20w22a and the issue still exists.
- Run the command
- Put on the leather helmet
- Press F5
- Look up or down depending on which F5 perspective you are in
→ The leather helmet turns white
Check the video or images for a better explanation