diff --git a/Userland/Libraries/LibWeb/Layout/Box.cpp b/Userland/Libraries/LibWeb/Layout/Box.cpp
index f35239c95f..8ddfc78a7c 100644
--- a/Userland/Libraries/LibWeb/Layout/Box.cpp
+++ b/Userland/Libraries/LibWeb/Layout/Box.cpp
@@ -41,6 +41,7 @@ bool overflow_value_makes_box_a_scroll_container(CSS::Overflow overflow)
     case CSS::Overflow::Scroll:
         return true;
     }
+    VERIFY_NOT_REACHED();
 }
 
 // https://www.w3.org/TR/css-overflow-3/#scroll-container