From 34b0f6f01406cf7846865cf3bc9e81a522d649a4 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Fri, 1 Feb 2019 11:09:14 +0300
Subject: [PATCH] Fix crash in group migration.

---
 Telegram/SourceFiles/info/info_wrap_widget.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Telegram/SourceFiles/info/info_wrap_widget.cpp b/Telegram/SourceFiles/info/info_wrap_widget.cpp
index b224f3a255..c9fac7699f 100644
--- a/Telegram/SourceFiles/info/info_wrap_widget.cpp
+++ b/Telegram/SourceFiles/info/info_wrap_widget.cpp
@@ -620,7 +620,16 @@ not_null<Ui::RpWidget*> WrapWidget::topWidget() const {
 }
 
 void WrapWidget::showContent(object_ptr<ContentWidget> content) {
-	_content = std::move(content);
+	if (auto old = std::exchange(_content, std::move(content))) {
+		old->hide();
+
+		// Content destructor may invoke closeBox() that will try to
+		// start layer animation. If we won't detach old content from
+		// its parent WrapWidget layer animation will be started with a
+		// partially destructed grand-child widget and result in a crash.
+		old->setParent(nullptr);
+		old.destroy();
+	}
 	_content->show();
 	_additionalScroll = 0;
 	//_anotherTabMemento = nullptr;