diff --git a/toolkit/themes/shared/in-content/common.inc.css b/toolkit/themes/shared/in-content/common.inc.css
index 660539c0efe7..138e54d3028b 100644
--- a/toolkit/themes/shared/in-content/common.inc.css
+++ b/toolkit/themes/shared/in-content/common.inc.css
@@ -77,6 +77,7 @@ xul|tabpanels {
   border: none;
   padding: 0;
   background-color: transparent;
+  color: inherit;
 }
 
 xul|tabs {