IconButton is using color `fg.default` instead of `fg.muted`

[maximedegreve]

Description

Throughout GitHub I suddenly noticed that all our IconButton components use a fg.default instead of fg.muted. This creates inconsistencies with high surfacing areas like the global navigation or UnderlineNav where the icons are always muted. It also doesn't match the previews in our documentation.

For context our icons inside a normal button are also fg.muted.

Steps to reproduce

Visit our storybook

Version

Latest

Browser

Safari

[joshblack]

@maximedegreve just wanted to confirm, are you also seeing this behavior in PVC, as well? Was taking a look over at: https://view-components-storybook.eastus.cloudapp.azure.com/view-components/lookbook/inspect/primer/beta/icon_button/default and it seems like it may also have the same issue but wanted to confirm first.

[langermank]

@joshblack yeah, this is a system-wide update. I'm happy to make the change in PVC if you wanna take the React side 👍