From cfcc5d085c465c0a13419dbd73ca91e47ef8bb74 Mon Sep 17 00:00:00 2001
From: Anton Kasyanov <antonk@remobjects.com>
Date: Mon, 4 Mar 2019 22:37:10 +0200
Subject: [PATCH] Fix for the detection of the currently active non-EVE app

---
 Eve-O-Preview/Services/Implementation/ThumbnailManager.cs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Eve-O-Preview/Services/Implementation/ThumbnailManager.cs b/Eve-O-Preview/Services/Implementation/ThumbnailManager.cs
index a7bb0c9..005927c 100644
--- a/Eve-O-Preview/Services/Implementation/ThumbnailManager.cs
+++ b/Eve-O-Preview/Services/Implementation/ThumbnailManager.cs
@@ -196,7 +196,12 @@ namespace EveOPreview.Services
 			}
 			else if (!isClientWindow)
 			{
-				this._externalApplication = foregroundWindowHandle;
+				// Under some circumstances Foreground WindowHandle can be zero
+				// (f.e. when Thumbnail is silently stealing focus from the currently open app)
+				if (foregroundWindowHandle != IntPtr.Zero)
+				{
+					this._externalApplication = foregroundWindowHandle;
+				}
 			}
 
 			// No need to minimize EVE clients when switching out to non-EVE window (like thumbnail)