This issues arrises when a skin PNG with Linear profile.

When I assign the skin to my account using the Launcher, it temporarily displays correctly.

However, upon launching Minecraft or re‑opening the Launcher, the skin will display with oversaturated colors.

These oversaturated colors persist in the actual game, and display to other players online as well.

Included for comparison and testing are the same skin saved as 8bit and 16bit PNGs

sRPG PNG	Linear profile PNG