From 31c7167c7556df4fa4846553ac642f0fb852d73a Mon Sep 17 00:00:00 2001
From: s2quake <han0210@netsgo.com>
Date: Thu, 21 Nov 2024 10:57:24 +0900
Subject: [PATCH] Fix: Collection was modified issue when slash executes

---
 Lib9c/ValidatorDelegation/AbstainHistory.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Lib9c/ValidatorDelegation/AbstainHistory.cs b/Lib9c/ValidatorDelegation/AbstainHistory.cs
index c90a987361..430d2c78cd 100644
--- a/Lib9c/ValidatorDelegation/AbstainHistory.cs
+++ b/Lib9c/ValidatorDelegation/AbstainHistory.cs
@@ -78,7 +78,7 @@ public List<PublicKey> FindToSlashAndAdd(IEnumerable<PublicKey> abstainList, lon
                 }
             }
 
-            foreach (var history in History)
+            foreach (var history in History.ToArray())
             {
                 history.Value.RemoveAll(abstainHeight => abstainHeight < lowerBound);
                 if (history.Value.Count == 0)