favicons have slightly smaller corner radius than the ones of outer box so that outer borders or inner negative space do not make thicker edges.
I cannot explain it well... these article should help understanding what I mean:

it seems favicons have the same or larger corner radius.
I agree this looks a bit strange. For reference here I have made it favIconBorderRadiusInPx cut in half to 4.

@ekager that looks great!
@AmyYLee can you review and approve this approach? If you are ok with it can you remove the Needs UX label and add the Ready for Eng label?
@AmyYLee can you review and approve this approach? If you are ok with it can you remove the Needs UX label and add the Ready for Eng label?
This looks good to me. @mheubusch
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I agree this looks a bit strange. For reference here I have made it
favIconBorderRadiusInPxcut in half to 4.