Similar issue to other mods which offer color selection -- Muffstick provides the player with 40+ color choices, but the current UI only gives access to 15 of them. Perhaps most importantly the "Transparent" option which leaves color unchanged is not accessible, since it's placed last on the color list:
JavaScript:
rbgSelColor(target, bimbo = false)
{
// ...
// Standard
colorList.push(["red", "Red"]);
colorList.push(["red-orange", "R.Orange"]);
colorList.push(["orange", "Orange"]);
colorList.push(["yellow-orange", "Y.Orange"]);
colorList.push(["yellow", "Yellow"]);
colorList.push(["yellow-green", "Y.Green"]);
colorList.push(["green", "Green"]);
colorList.push(["teal", "Teal"]);
colorList.push(["cerulean", "Cerulean"]);
colorList.push(["blue", "Blue"]);
colorList.push(["indigo", "Indigo"]);
colorList.push(["purple", "Purple"]);
colorList.push(["lavender", "Lavender"]);
colorList.push(["pink", "Pink"]);
colorList.push(["rose", "Rose"]);
colorList.push(["peach", "Peach"]);
colorList.push(["brown", "Brown"]);
colorList.push(["hazel", "Hazel"]);
colorList.push(["white", "White"]);
colorList.push(["black", "Black"]);
// Gemstone
colorList.push(["crimson", "Crimson"]);
colorList.push(["garnet", "Garnet"]);
colorList.push(["ruby", "Ruby"]);
colorList.push(["citrine", "Citrine"]);
colorList.push(["topaz", "Topaz"]);
colorList.push(["amber", "Amber"]);
colorList.push(["peridot", "Peridot"]);
colorList.push(["emerald", "Emerald"]);
colorList.push(["jade", "Jade"]);
colorList.push(["turquoise", "Turquoise"]);
colorList.push(["aquamarine", "Aquamarine"]);
colorList.push(["lapis", "Lapis"]);
colorList.push(["sapphire", "Sapphire"]);
colorList.push(["violet", "Violet"]);
colorList.push(["amethyst", "Amethyst"]);
colorList.push(["opal", "Opal"]);
colorList.push(["pearl", "Pearl"]);
// Metallic
colorList.push(["copper", "Copper"]);
colorList.push(["silver", "Silver"]);
colorList.push(["gold", "Gold"]);
colorList.push(["platinum", "Platinum"]);
colorList.push(["sable", "Sable"]);
// None
colorList.push(["null", "Transparent"]);
// ...