From 47d2ecf62964a210d371dc68c558d1282ed7e450 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Fri, 19 Feb 2021 17:53:11 +0400
Subject: [PATCH] Fix a possible crash in Clear History.

---
 Telegram/SourceFiles/history/history_message.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Telegram/SourceFiles/history/history_message.cpp b/Telegram/SourceFiles/history/history_message.cpp
index 42f4fc544b..8588c20f97 100644
--- a/Telegram/SourceFiles/history/history_message.cpp
+++ b/Telegram/SourceFiles/history/history_message.cpp
@@ -1391,12 +1391,15 @@ void HistoryMessage::applyEdition(const MTPDmessage &message) {
 
 void HistoryMessage::applyEdition(const MTPDmessageService &message) {
 	if (message.vaction().type() == mtpc_messageActionHistoryClear) {
+		const auto wasGrouped = history()->owner().groups().isGrouped(this);
 		setReplyMarkup(nullptr);
 		refreshMedia(nullptr);
 		setEmptyText();
 		setViewsCount(-1);
 		setForwardsCount(-1);
-
+		if (wasGrouped) {
+			history()->owner().groups().unregisterMessage(this);
+		}
 		finishEditionToEmpty();
 	}
 }