The colour of the kerbals' skin: one colour for everyone, a different one for each kerbal, or your own choice for any one of them. Only the skin changes; hair, eyes, mouths and suits stay as they are.
For Kerbal Space Program 1.12.x. Needs Keystone, which comes in the download.

Copy the Keystone and KerbalSkins folders from the download into your KSP GameData.
Open the Keystone window (the keystone button on the game's toolbar, or Option-K on a Mac, Alt-K elsewhere), turn to Kerbal Skins and switch on Change skin colours.

as the rest takes it away again.A kerbal's own colour is remembered by name, in every save. The cockpit view, the portraits and the kerbal outside the ship all show it.
More: how it works and what it costs, choosing colours, limits, building it yourself.
github.com/IshiakiZ/ksp-kerbal-skins: the source, the wiki with the long description, and where to report a fault. Licence: MIT.
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