Currently there are style discrepancies between the "Case sensitive icon" in the Combo component in Angular and WC:

Bootstrap:
The icon in Angular has a background and a different color than the one in WC:

Light:

Dark:

Fluent:
Again the icon in Angular has a background and a different color than the one in WC:

Light:

Dark:

Indigo:
Here the icon color is the same, but the icon opacity in Angular is set to 0.54, while in WC is set to 1.

Light:

Dark:

Material:
In Angular, the icon size is smaller than in WC, and its opacity is set to 0.54, just like in Indigo.

Light:

Dark: