Ticket #51445: 51445.2.diff

src/wp-content/themes/twentyfifteen/style.css

@@ -1398 +1398 @@
         text-transform: uppercase;
 }
 
-.widget > :last-child {
+.widget > :last-child,
+.widget > nav > :last-child {
         margin-bottom: 0;
 }
 

src/wp-content/themes/twentysixteen/style.css

@@ -1413 +1413 @@
 }
 
 .widget-area > :last-child,
-.widget > :last-child {
+.widget > :last-child,
+.widget > nav > :last-child {
         margin-bottom: 0;
 }