This came up on the Discord not too long ago, so I will mirror the info I wrote there. Tldr: the highlights use colors from your Color Theme, but the forced transparency of the highlight somewhat hinders visibility of even the brightest colors.
onSurface and primary are the color slots you are looking for. There are at least two different highlights
As far as which is used where:
- onSurface color is used on the Navigation Bar and Now Playing screens
- primary is used on Home page and Library screens
Do note that the UI highlight has forced transparency on it, so you won’t get any solid, vibrant color on it
Edit: copied the last bit of info out of the screenshot
