diff --git a/src/manifest.json b/src/manifest.json
index 6a45a3c..6f2e429 100644
--- a/src/manifest.json
+++ b/src/manifest.json
@@ -22,7 +22,8 @@
     "storage",
     "alarms",
     "notifications",
-    "contextMenus"
+    "contextMenus",
+    "downloads"
   ],
   "host_permissions": [
     "https://www.googleapis.com/*",
diff --git a/src/popup/actions.js b/src/popup/actions.js
index 68dee33..73532f3 100644
--- a/src/popup/actions.js
+++ b/src/popup/actions.js
@@ -81,13 +81,15 @@ export async function downloadAttachment(accountId, messageId, attachment) {
   }
   const blob = new Blob([bytes], { type: attachment.mimeType || 'application/octet-stream' });
   const url = URL.createObjectURL(blob);
-  const a = document.createElement('a');
-  a.href = url;
-  a.download = attachment.filename || 'attachment';
-  document.body.appendChild(a);
-  a.click();
-  document.body.removeChild(a);
-  setTimeout(() => URL.revokeObjectURL(url), 1000);
+  try {
+    await api.downloads.download({
+      url,
+      filename: attachment.filename || 'attachment',
+      saveAs: false,
+    });
+  } finally {
+    setTimeout(() => URL.revokeObjectURL(url), 5000);
+  }
 }
 
 export async function bulkAction(action) {
diff --git a/src/popup/detail.js b/src/popup/detail.js
index ae65148..72db713 100644
--- a/src/popup/detail.js
+++ b/src/popup/detail.js
@@ -59,10 +59,12 @@ function buildAttachmentItem(accountId, messageId, att) {
 
   item.addEventListener('click', async () => {
     item.disabled = true;
+    item.classList.remove('attachment-item--error');
     try {
       await downloadAttachment(accountId, messageId, att);
-    } catch {
-      // Silently fail — the file icon just stays enabled on next click.
+    } catch (err) {
+      console.error('Attachment download failed:', err);
+      item.classList.add('attachment-item--error');
     } finally {
       item.disabled = false;
     }
diff --git a/src/popup/popup.css b/src/popup/popup.css
index 5cfced3..2050a2c 100644
--- a/src/popup/popup.css
+++ b/src/popup/popup.css
@@ -699,6 +699,11 @@ body {
   cursor: wait;
 }
 
+.attachment-item--error {
+  border-color: var(--danger);
+  color: var(--danger);
+}
+
 .attachment-icon {
   color: var(--text-secondary);
   flex-shrink: 0;