diff --git a/src/ui/models/EmailTreeModel.cpp b/src/ui/models/EmailTreeModel.cpp
index f8a0881..69cd1c9 100644
--- a/src/ui/models/EmailTreeModel.cpp
+++ b/src/ui/models/EmailTreeModel.cpp
@@ -20,7 +20,9 @@ EmailTreeModel::~EmailTreeModel()
 void EmailTreeModel::deleteTree(TreeItem* item)
 {
     if (!item) return;
-    qDeleteAll(item->children);
+    // TreeItem::~TreeItem already deletes its children recursively (qDeleteAll(children)).
+    // Only delete the node itself — calling qDeleteAll(children) here first would
+    // double-free (the dtor frees them again) and SIGSEGV on teardown in debug builds.
     delete item;
 }