From ea83d040e60d179248ac6213cf53b3343e95b371 Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 24 Nov 2021 16:46:40 +0100
Subject: [PATCH] Viewports: fix missing default per-window value for
 ParentViewportId due to zero-cleared in-window instance (#4756)

Broken by 2080d12b
---
 imgui.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/imgui.cpp b/imgui.cpp
index 3663a46fa..0621e7324 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -3092,6 +3092,7 @@ ImGuiWindow::ImGuiWindow(ImGuiContext* context, const char* name) : DrawListInst
     DrawList = &DrawListInst;
     DrawList->_Data = &context->DrawListSharedData;
     DrawList->_OwnerName = Name;
+    IM_PLACEMENT_NEW(&WindowClass) ImGuiWindowClass();
 }
 
 ImGuiWindow::~ImGuiWindow()