diff --git a/ui/src/components/Sidebar.tsx b/ui/src/components/Sidebar.tsx
index c1b57f7e0a8..ae5e83d433c 100644
--- a/ui/src/components/Sidebar.tsx
+++ b/ui/src/components/Sidebar.tsx
@@ -65,7 +65,7 @@ export function Sidebar() {
         </Button>
       </div>
 
-      <nav className="flex-1 min-h-0 overflow-y-auto scrollbar-none flex flex-col gap-4 px-3 py-2">
+      <nav className="flex-1 min-h-0 overflow-y-auto scrollbar-auto-hide flex flex-col gap-4 px-3 py-2">
         <div className="flex flex-col gap-0.5">
           {/* New Issue button aligned with nav items */}
           <button
diff --git a/ui/src/index.css b/ui/src/index.css
index cacbdb18405..1842f4f7057 100644
--- a/ui/src/index.css
+++ b/ui/src/index.css
@@ -178,6 +178,17 @@
   background: oklch(0.5 0 0);
 }
 
+/* Auto-hide scrollbar: transparent by default, visible on container hover */
+.scrollbar-auto-hide::-webkit-scrollbar-thumb {
+  background: transparent !important;
+}
+.scrollbar-auto-hide:hover::-webkit-scrollbar-thumb {
+  background: oklch(0.4 0 0) !important;
+}
+.scrollbar-auto-hide:hover::-webkit-scrollbar-thumb:hover {
+  background: oklch(0.5 0 0) !important;
+}
+
 /* Expandable dialog transition for max-width changes */
 [data-slot="dialog-content"] {
   transition: max-width 200ms cubic-bezier(0.16, 1, 0.3, 1);