diff --git a/src/browser/app/profile/zen-browser.js b/src/browser/app/profile/zen-browser.js
index 89ae3efec..adff0d1de 100644
--- a/src/browser/app/profile/zen-browser.js
+++ b/src/browser/app/profile/zen-browser.js
@@ -71,7 +71,7 @@ pref('zen.tabs.vertical', true);
 pref('zen.tabs.vertical.right-side', false);
 pref('zen.theme.accent-color', "#aac7ff");
 pref('zen.theme.border-radius', 10); // In pixels
-pref('zen.theme.content-element-separation', 10); // In pixels
+pref('zen.theme.content-element-separation', 4); // In pixels
 pref('zen.theme.toolbar-themed', true);
 pref('zen.theme.pill-button', false);
 pref('zen.view.compact', false);
diff --git a/src/browser/base/content/zen-styles/zen-browser-container.css b/src/browser/base/content/zen-styles/zen-browser-container.css
index d39b2cdea..3ddf1a3f8 100644
--- a/src/browser/base/content/zen-styles/zen-browser-container.css
+++ b/src/browser/base/content/zen-styles/zen-browser-container.css
@@ -1,13 +1,35 @@
 :root:not([inDOMFullscreen='true']):not([chromehidden~='location']):not([chromehidden~='toolbar']) {
   & #tabbrowser-tabbox #tabbrowser-tabpanels .browserSidebarContainer {
     width: -moz-available;
-    box-shadow: 0 0 0 1px var(--zen-colors-border);
-    clip-path: inset(-5px -5px -5px round var(--zen-webview-border-radius, var(--zen-border-radius)));
     border-radius: var(--zen-webview-border-radius, var(--zen-border-radius));
     transform: translate3d(0, 0, 0);
-    overflow: hidden;
+    position: relative;
 
     /* This fixes an issue with the left border */
     margin-left: 2px;
+    --uc-tweak-rounded-corners-shadow-color: var(--zen-colors-border);
+
+    --uc-tweak-rounded-corners-shadow:
+      0 -.8px 0 0 var(--uc-tweak-rounded-corners-shadow-color),
+      0 0.5px 1px 1px var(--uc-tweak-rounded-corners-shadow-color),
+      0 1px 1px var(--uc-tweak-rounded-corners-shadow-color);
+
+    box-shadow: var(--uc-tweak-rounded-corners-shadow) !important;
+
+    /* Use pseudo element overlay to simulate rounded corners, similar to the
+     * tab corners, fixes bug with backdrop-filter. */
+    &::after {
+      content: "";
+      position: absolute;
+      inset: 0;
+      border-radius: inherit;
+      /* Draw toolbar background on the negative corner space, then draw the
+       * same shadow from the browser window on top. */
+      box-shadow:
+        var(--uc-tweak-rounded-corners-shadow, 0 0 transparent),
+        0 0 0 16px var(--zen-themed-toolbar-bg) !important;
+      clip-path: inset(0);
+      pointer-events: none;
+    }
   }
 }
diff --git a/src/browser/base/content/zen-styles/zen-decks.css b/src/browser/base/content/zen-styles/zen-decks.css
index 2fe4c663b..871c15996 100644
--- a/src/browser/base/content/zen-styles/zen-decks.css
+++ b/src/browser/base/content/zen-styles/zen-decks.css
@@ -26,7 +26,7 @@
 }
 
 #tabbrowser-tabpanels[zen-split-view='true'] .browserSidebarContainer[zen-split-active='true'] {
-  box-shadow: 0 0 0 2px var(--zen-primary-color) !important;
+  --uc-tweak-rounded-corners-shadow-color: var(--zen-primary-color) !important;
 }
 
 #tabbrowser-tabpanels:has(> [zen-split='true']) {