diff --git a/sidebar/stolen-data-cluster.tsx b/sidebar/stolen-data-cluster.tsx
index ecaea10..615db0b 100644
--- a/sidebar/stolen-data-cluster.tsx
+++ b/sidebar/stolen-data-cluster.tsx
@@ -52,6 +52,7 @@ function StolenDataRow({ entry }: { entry: StolenDataEntry }) {
           width: "100px",
           overflowWrap: "anywhere",
         }}
+        title={"Źródło: " + entry.source}
         onClick={() => entry.toggleMark()}
       >
         {entry.name}