[meld/ui-next] Fix temporary actionback background with multiple tabs

[Kai Willadsen <kaiw src gnome org>]

commit 8035579330f3c9aafad66e37ca024ab0c80a8879
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sun Mar 3 07:59:54 2019 +1000

    Fix temporary actionback background with multiple tabs

 data/meld.css | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/data/meld.css b/data/meld.css
index 95734b2e..a1bd6389 100644
--- a/data/meld.css
+++ b/data/meld.css
@@ -11,6 +11,7 @@
 }
 
 .meld-actionbar {
+  background-color: @theme_bg_color;
   padding: 6px;
 }