From 42a71ccbbd2937d270e46c1688b9411a7f82f13d Mon Sep 17 00:00:00 2001
From: Uwe <donovaly@users.noreply.github.com>
Date: Fri, 4 Mar 2022 04:43:34 +0100
Subject: [PATCH] [Gui] DocumentObserver: re-add a header

---
 src/Gui/DocumentObserver.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Gui/DocumentObserver.h b/src/Gui/DocumentObserver.h
index ed2471b77b..4c550ac620 100644
--- a/src/Gui/DocumentObserver.h
+++ b/src/Gui/DocumentObserver.h
@@ -23,6 +23,7 @@
 #ifndef GUI_DOCUMENTOBSERVER_H
 #define GUI_DOCUMENTOBSERVER_H
 
+#include <Base/BaseClass.h>
 #include <boost_signals2.hpp>