It's not really a workaround, all of those icons are valid when it comes to YaST, however previous batch of YaST icons into Breeze was build on idea that icon xyz-abc.svg will fallback to xyz.svg inside the same icon theme. In QIcon::fromTheme that is the case IF icon xyz-abc.svg does not exist in hicolor or any other fallback theme.

That happens in Inkscape and other renderers with uneven (133%, 146% etc) magnification. When rendering also sometimes you will get a darker border when there is something dark behind an object. I used that to my advantage with new YaST Package Management icons