Fix header image not being rendered

public/typo3conf/ext/ep_theme/Resources/Private/Partials/Product/HeaderDetail.html

@@ -1,7 +1,7 @@
 {namespace v=FluidTYPO3\Vhs\ViewHelpers}
 {namespace ep=EP\EpTheme\ViewHelpers}
 <div class="container ep-product-detail product-header">
-    <div class="ep-product-detail-bg season-{product.region.season}"></div>
+    <div class="ep-product-detail-bg season-{product.region.season -> v:or(alternative: 'w')}"></div>
     <div class="col-sm-6 col-sm-offset-1 pull-right">
         <div class="slider slider--product">
             <div class="slider__items">