Operating system: Windows-7-6.1.7601-SP1 64 Bits
Graphics card: GeForce GTX 1060 6GB/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 419.35
Broken: version: 2.80 (sub 55), branch: blender2.7, commit date: 2019-04-09 18:12, hash: rB009dbc2bc9fb
Stumbled across this behaviour when comparing the double entry in the Gradient subpanel. Here the secondary color gets displayed too. And when you compare those two identical secondary colors, then the one in the color picker is much duller. But it is the same color. The difference is very visible at the turquoise color.
Same in the panel in the header. So something seems to be broken here with the display of this color element.
Short description of error
[Please fill out a short description of the error here]
Exact steps for others to reproduce the error
[Please describe the exact steps needed to reproduce the issue]
[Based on the default startup or an attached .blend file (as simple as possible)]
Open Blender, add object, switch to texture paint and add a texture.
Open the Brush panel, open color picker and gradient panel. Tick gradient to have the tools. Compare the secondary colors.