Dashboard: Fix empty panels after scrolling on Safari/iOS (#26495)

public/sass/components/_navbar.scss

@@ -5,6 +5,7 @@
   padding: 0 16px 0 60px;
   display: flex;
   flex-grow: 0;
+  flex-shrink: 0;
   border-bottom: 1px solid transparent;
   transition-duration: 350ms;
   transition-timing-function: ease-in-out;

public/sass/pages/_dashboard.scss

@@ -13,6 +13,7 @@
   width: 100%;
   flex-grow: 1;
   min-height: 0;
+  display: flex;
 }
 
 .dashboard-content {