diff --git a/frontend/src/components/ai/SessionList.tsx b/frontend/src/components/ai/SessionList.tsx
index 26d50b0..bbd4596 100644
--- a/frontend/src/components/ai/SessionList.tsx
+++ b/frontend/src/components/ai/SessionList.tsx
@@ -88,6 +88,7 @@ function TreeItem({
         <div
           draggable
           onDragStart={(e) => {
+            if (e.button !== 0) { e.preventDefault(); return; }
             e.dataTransfer.setData('text/plain', `folder:${node.folder!.id}`);
             e.dataTransfer.effectAllowed = 'move';
             onDragFolder(node.folder!.id);