From 553ec7537c30636ddf6cbc157373477fb2e9da41 Mon Sep 17 00:00:00 2001
From: Paul Cornett <paulcor@users.noreply.github.com>
Date: Wed, 9 Nov 2016 20:06:26 -0800
Subject: [PATCH] Fix non-default window background color with GTK+ >= 3.20

GTK+ no longer automatically paints non-default window background. See #17586

(cherry picked from commit 9bb5d0435a4cce5bcb7b3956cb730f59c37ea5f6)
---
 src/gtk/window.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/gtk/window.cpp b/src/gtk/window.cpp
index 0826e06..bca5443 100644
--- a/src/gtk/window.cpp
+++ b/src/gtk/window.cpp
@@ -4238,6 +4238,15 @@ void wxWindowGTK::GTKSendPaintEvents(const GdkRegion* region)
                                     0, 0, w, h);
 #endif // !__WXGTK3__
             }
+#ifdef __WXGTK3__
+            else if (m_backgroundColour.IsOk() && gtk_check_version(3,20,0) == NULL)
+            {
+                cairo_save(cr);
+                gdk_cairo_set_source_rgba(cr, m_backgroundColour);
+                cairo_paint(cr);
+                cairo_restore(cr);
+            }
+#endif
             break;
 
         case wxBG_STYLE_PAINT: