I had the same issue.
I fixed it by coping the icon "/usr/share/icons/hicolor/128x128/apps/softwarecenter.svg" over the "/usr/share/icons/hicolor/scalable/apps/softwarecenter.svg" icon.
I had the same issue.
I fixed it by coping the icon "/usr/share/ icons/hicolor/ 128x128/ apps/softwarece nter.svg" over the "/usr/share/ icons/hicolor/ scalable/ apps/softwarece nter.svg" icon.