diff --git a/src/frontend/features/cleaner/cleaner-section.tsx b/src/frontend/features/cleaner/cleaner-section.tsx
index d403ab9..8461e4a 100644
--- a/src/frontend/features/cleaner/cleaner-section.tsx
+++ b/src/frontend/features/cleaner/cleaner-section.tsx
@@ -43,7 +43,7 @@ export function CleanerSection({
 
   function confirmCleanup() {
     if (report) {
-      startCleanup(useCleanerViewModelHook.viewModel);
+      void startCleanup(useCleanerViewModelHook.viewModel);
     }
     setShowConfirmDialog(false);
   }
diff --git a/src/frontend/features/cleaner/cleaner.types.ts b/src/frontend/features/cleaner/cleaner.types.ts
index 1e6cf6f..d1f3e35 100644
--- a/src/frontend/features/cleaner/cleaner.types.ts
+++ b/src/frontend/features/cleaner/cleaner.types.ts
@@ -16,7 +16,7 @@ export type CleanerContextType = {
   diskSpace: number;
   sectionKeys: CleanerSectionKey[];
   generateReport: (force?: boolean) => Promise<void>;
-  startCleanup: (viewModel: CleanerViewModel) => void;
+  startCleanup: (viewModel: CleanerViewModel) => Promise<void>;
   stopCleanup: () => void;
   setInitialCleaningState: () => void;
 };
diff --git a/src/frontend/features/cleaner/components/cleanup-confirm-dialog.tsx b/src/frontend/features/cleaner/components/cleanup-confirm-dialog.tsx
index f8f15c4..5e13a3f 100644
--- a/src/frontend/features/cleaner/components/cleanup-confirm-dialog.tsx
+++ b/src/frontend/features/cleaner/components/cleanup-confirm-dialog.tsx
@@ -18,7 +18,7 @@ export function CleanupConfirmDialog({ isVisible, onConfirm, onCancel, useTransl
   return (
     <div className="fixed inset-0 z-50 flex items-center justify-center">
       {/* Backdrop */}
-      <div className="bg-opacity-50 absolute inset-0 bg-black backdrop-blur-sm" onClick={onCancel} />
+      <div className="bg-opacity-50 absolute inset-0 bg-black backdrop-blur-sm" onClick={onCancel} aria-hidden="true" />
 
       {/* Dialog */}
       <div className="bg-surface relative mx-4 w-full max-w-md rounded-lg p-6 shadow-xl dark:bg-gray-800">
diff --git a/src/frontend/features/cleaner/components/cleanup-size-indicator.tsx b/src/frontend/features/cleaner/components/cleanup-size-indicator.tsx
index 9ac7e65..d3b8f12 100644
--- a/src/frontend/features/cleaner/components/cleanup-size-indicator.tsx
+++ b/src/frontend/features/cleaner/components/cleanup-size-indicator.tsx
@@ -41,7 +41,7 @@ export function CleanupSizeIndicator({ selectedSize, totalSize, segmentDetails,
 
                     acc.elements.push(
                       <path
-                        key={index}
+                        key={`segment-${index}`}
                         d="M 20 100 A 80 80 0 0 1 180 100"
                         fill="none"
                         stroke={segment.color}
diff --git a/src/frontend/features/cleaner/components/section-detail-header.tsx b/src/frontend/features/cleaner/components/section-detail-header.tsx
index 2dfa37c..3bbe7b4 100644
--- a/src/frontend/features/cleaner/components/section-detail-header.tsx
+++ b/src/frontend/features/cleaner/components/section-detail-header.tsx
@@ -31,7 +31,7 @@ export function SectionDetailHeader({
   return (
     <div className="dark:bg-gray-5 flex items-center justify-between p-4">
       <div className="flex items-center gap-3">
-        <div className="flex items-center gap-1 text-blue-600 hover:cursor-pointer dark:text-blue-400" onClick={onClose}>
+        <div className="flex items-center gap-1 text-blue-600 hover:cursor-pointer dark:text-blue-400" onClick={onClose} aria-hidden="true">
           <CaretDoubleRight color="#0066ff" weight="bold" />
         </div>
         <h3 className="text-lg font-semibold text-gray-900 dark:text-gray-100">{sectionConfig[sectionName].name}</h3>
diff --git a/src/frontend/features/cleaner/components/section-detail-menu.tsx b/src/frontend/features/cleaner/components/section-detail-menu.tsx
index 0b37385..3fd1788 100644
--- a/src/frontend/features/cleaner/components/section-detail-menu.tsx
+++ b/src/frontend/features/cleaner/components/section-detail-menu.tsx
@@ -32,11 +32,18 @@ export function SectionDetailMenu({
   onToggleItem,
   useTranslationContext,
 }: Readonly<Props>) {
-  if (!sectionName) return null;
+  const parentRef = useRef<HTMLDivElement>(null);
 
   const sectionData = report[sectionName];
   const sectionViewModel = viewModel[sectionName];
-  if (!sectionViewModel) return null;
+  const items = sectionData?.items || [];
+
+  const virtualizer = useVirtualizer({
+    count: items.length,
+    getScrollElement: () => parentRef.current,
+    estimateSize: () => 80,
+    overscan: 10,
+  });
 
   const stats = getSectionStats({ viewModel: sectionViewModel, allItems: sectionData.items });
 
@@ -50,16 +57,6 @@ export function SectionDetailMenu({
     }
   }
 
-  const parentRef = useRef<HTMLDivElement>(null);
-  const items = sectionData.items;
-
-  const virtualizer = useVirtualizer({
-    count: items.length,
-    getScrollElement: () => parentRef.current,
-    estimateSize: () => 80,
-    overscan: 10,
-  });
-
   return (
     <div
       className={
diff --git a/src/frontend/features/cleaner/components/section-item.tsx b/src/frontend/features/cleaner/components/section-item.tsx
index 89caf85..cc58f03 100644
--- a/src/frontend/features/cleaner/components/section-item.tsx
+++ b/src/frontend/features/cleaner/components/section-item.tsx
@@ -53,6 +53,7 @@ export function SectionItem({
 
         <div
           className="flex flex-1 items-end justify-end"
+          aria-hidden="true"
           onClick={(e) => {
             e.stopPropagation();
             onToggleSectionExpansion(sectionName);