diff --git a/gtk2_ardour/widget_list.rc b/gtk2_ardour/widget_list.rc
index 82e2e110b9..689bd7096a 100644
--- a/gtk2_ardour/widget_list.rc
+++ b/gtk2_ardour/widget_list.rc
@@ -219,3 +219,4 @@ widget "*transport active option button" style:highest "small_text"
 widget "*plugin bypass button" style:highest "small_text"
 widget "*punch button" style:highest "small_text"
 widget "*lock button" style:highest "large_bold_text"
+widget "*ooltip*" style:highest "tooltip"