Looks like [this CSS](https://github.com/smartstore/SmartStoreNET/blob/4.x/src/Presentation/SmartStore.Web/Themes/Flex/Content/_megamenu.scss#L269) is causing this. From [forum](http://community.smartstore.com/index.php?/topic/50505-v410-mega-menu-hintergrund-bild-link-funktioniert-in-frontend-nicht/).
