Duotone icons  looks like  regular in master branch
Hello!
Thank you for your great icons,

After upgrade from 1.4 to master,  not 2.0.0 due to the const problem; I tested the PhosphorIconsDuotone implementation.
with the code :
Icon(PhosphorIconsDuotone.bookmarkSimple)

look exactly like 
Icon(PhosphorIconsRegular.bookmarkSimple)

best regards,

Alexandre

