From 1807458c66788936dd5b276a3173e029d3c2237a Mon Sep 17 00:00:00 2001
From: Kevin Sawicki <kevinsawicki@gmail.com>
Date: Thu, 29 Sep 2016 11:49:24 -0700
Subject: [PATCH] Only begin sheet when no sheet parent

---
 atom/browser/native_window_mac.mm | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/atom/browser/native_window_mac.mm b/atom/browser/native_window_mac.mm
index 931d6355f11f..98e8d4b65659 100644
--- a/atom/browser/native_window_mac.mm
+++ b/atom/browser/native_window_mac.mm
@@ -740,8 +740,9 @@ bool NativeWindowMac::IsFocused() {
 
 void NativeWindowMac::Show() {
   if (is_modal() && parent()) {
-    [parent()->GetNativeWindow() beginSheet:window_
-                          completionHandler:^(NSModalResponse) {}];
+    if ([window_ sheetParent] == nil)
+      [parent()->GetNativeWindow() beginSheet:window_
+                            completionHandler:^(NSModalResponse) {}];
     return;
   }