[gtk/kill-popup-windows: 12/13] reftests: Fix background-window-transparent

[Matthias Clasen <matthiasc src gnome org>]

commit 6def85ce6e617dfabe23748535c8b148b1b3b4bd
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Jan 8 22:14:00 2020 -0500

    reftests: Fix background-window-transparent
    
    EXplicitly color the titlebar background to avoid
    the issue.

 testsuite/reftests/background-window-transparent.css | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/testsuite/reftests/background-window-transparent.css 
b/testsuite/reftests/background-window-transparent.css
index ecfec47906..9d3bc88263 100644
--- a/testsuite/reftests/background-window-transparent.css
+++ b/testsuite/reftests/background-window-transparent.css
@@ -1,5 +1,6 @@
 @import "reset-to-defaults.css";
 
+window .titlebar,
 window { background-color: lime; }
 
 #reference * { background-color: lime; }