diff --git a/src/legacy/ui/public/chrome/directives/header_global_nav/_header_global_nav.scss b/src/legacy/ui/public/chrome/directives/header_global_nav/_header_global_nav.scss
index 96d6cf52a0c9c..2b841eca6e01d 100644
--- a/src/legacy/ui/public/chrome/directives/header_global_nav/_header_global_nav.scss
+++ b/src/legacy/ui/public/chrome/directives/header_global_nav/_header_global_nav.scss
@@ -15,6 +15,7 @@
   // SASSTODO: Find an actual solution
   .euiFlyout {
     top: $euiHeaderChildSize;
+    height: calc(100% - #{$euiHeaderChildSize});
   }
 }