From a68bfab59624d489ab697b3d6b12af28ed6a53b9 Mon Sep 17 00:00:00 2001
From: f321x <f@f321x.com>
Date: Mon, 18 Aug 2025 10:03:24 +0200
Subject: [PATCH] swaps: improve preimage extraction logic

---
 electrum/submarine_swaps.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/electrum/submarine_swaps.py b/electrum/submarine_swaps.py
index aa5399c50..9a968daf8 100644
--- a/electrum/submarine_swaps.py
+++ b/electrum/submarine_swaps.py
@@ -384,7 +384,7 @@ class SwapManager(Logger):
     def extract_preimage(cls, swap: SwapData, claim_tx: Transaction) -> Optional[bytes]:
         for txin in claim_tx.inputs():
             witness = txin.witness_elements()
-            if not witness:
+            if not witness or len(witness) < 2:
                 # tx may be unsigned
                 continue
             preimage = witness[1]