notebook: Document the .dnd style class

We should aim to document all style classes that themes
can encounter during the normal operation of a widget.

diff --git a/gtk/gtknotebook.c b/gtk/gtknotebook.c
index f0eef0066fbdda6174770ea75c0245cbf896dd6a..68b823088385e358f31f37dced46b300a63809d1 100644 (file)
--- a/gtk/gtknotebook.c
+++ b/gtk/gtknotebook.c
@@ -135,6 +135,8 @@
  * The header node gets one of the style class .top, .bottom,
  * .left or .right, depending on where the tabs are placed. For
  * reorderable pages, the tab node gets the .reorderable-page class.
+ *
+ * A tab node gets the .dnd style class while it is moved with drag-and-drop.
  */