From 831e2c920edf62b1254587418a4f1968de3dc37e Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Fri, 21 Aug 2020 18:44:56 +0200
Subject: [PATCH] Docking, Viewport: Fixed a rare edge-case if the window
 targetted by CTRL+Tab stops being rendered.

---
 imgui.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/imgui.cpp b/imgui.cpp
index ac94fc2e..110b73d2 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -4386,9 +4386,10 @@ static void ImGui::EndFrameDrawDimmedBackgrounds()
         }
 
     // Draw modal whitening background between CTRL-TAB list
-    if (dim_bg_for_window_list)
+    if (dim_bg_for_window_list && g.NavWindowingTargetAnim->Active)
     {
         // Choose a draw list that will be front-most across all our children
+        // In the unlikely case that the window wasn't made active we can't rely on its drawlist and skip rendering all-together.
         ImGuiWindow* window = g.NavWindowingTargetAnim;
         ImDrawList* draw_list = FindFrontMostVisibleChildWindow(window->RootWindow)->DrawList;
         draw_list->PushClipRectFullScreen();