diff --git a/src/browser/base/content/zen-styles/zen-compact-mode.css b/src/browser/base/content/zen-styles/zen-compact-mode.css
index 1d890b0af..bb0f98601 100644
--- a/src/browser/base/content/zen-styles/zen-compact-mode.css
+++ b/src/browser/base/content/zen-styles/zen-compact-mode.css
@@ -98,7 +98,7 @@
 
     #navigator-toolbox:not([animate='true']) #titlebar {
       box-shadow: var(--zen-big-shadow);
-      border-radius: var(--zen-native-inner-radius);
+      border-radius: calc(var(--zen-native-inner-radius) + var(--zen-element-separation) / 4);
       padding: var(--zen-toolbox-padding) !important;
       position: relative;
       background: var(--zen-dialog-background);