ensure msp-layout-region background

src/mol-plugin/skin/base/components/transformer.scss

-.msp-transformer {    
-    
+.msp-transformer {
+
     .msp-entity-badge {
         position: absolute;
         top: 0;
@@ -15,24 +15,24 @@
 }
 
 .msp-transformer-wrapper {
-    position: relative;    
+    position: relative;
 }
 
-.msp-transformer-wrapper {   
-    
+.msp-transformer-wrapper {
+
     .msp-entity-badge {
         left: 0;
         top: 0;
     }
-    
+
     &:first-child {
         .msp-panel-description-content {
             top: $row-height + 1;
         }
     }
-    
+
     &:not(:first-child) {
-        .msp-panel-description-content {            
+        .msp-panel-description-content {
             bottom: $row-height + 1;
         }
     }

src/mol-plugin/skin/base/layout/common.scss

@@ -13,7 +13,7 @@
 
 .msp-layout-region {
     overflow: hidden;
-    background: $default-background;
+    background: $default-background !important;
 }
 
 .msp-layout-static, .msp-layout-scrollable {