popovermenubar: Use markdown for css tree

diff --git a/gtk/gtkpopovermenubar.c b/gtk/gtkpopovermenubar.c
index 1dd1497e4c9243babbacdcb4e96d757c12dadd00..4c5088c734cce7550ae67c693661dc2af2e08f71 100644 (file)
--- a/gtk/gtkpopovermenubar.c
+++ b/gtk/gtkpopovermenubar.c
@@ -31,13 +31,13 @@
  *
  * # CSS nodes
  *
- * |[<!-- language="plain" -->
+ * ```
  * menubar
  * ├── item[.active]
  * ┊   ╰── popover
  * ╰── item
  *     ╰── popover
- * ]|
+ * ```
  *
  * `GtkPopoverMenuBar` has a single CSS node with name menubar, below which
  * each item has its CSS node, and below that the corresponding popover.