diff --git a/CHANGES.md b/CHANGES.md
index e514a87ffe0..c75214cc62c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -4,6 +4,13 @@ moodle-theme_boost_union
 Changes
 -------
 
+### Unreleased
+
+* 2024-04-08 - Bugfix: Smart menu 3rd level submenus were being cut-off in responsive / mobile view, resolves #356.
+               Please note: This is a comparably large change which effectively replaces the flyout menus in the main navigation area and the menu bar area with the 'sliding door' submenu behaviour which has been used in the user menu only up to now.
+* 2024-04-08 - Bugfix: Smart menu 3rd level submenus had a font color which differed from the 2nd level and might have been even invisible, resolves #459.
+* 2024-04-08 - Bugfix: Long smart menus were not scrollable vertically, resolves #406.
+
 ### v4.3-r11
 
 * 2024-04-01 - Bugfix: Site support form success message is now shown above advert tiles / the slider on frontpage, partly resolves #488.
diff --git a/classes/output/navigation/primary.php b/classes/output/navigation/primary.php
index 23767bebddd..f70c1552f60 100644
--- a/classes/output/navigation/primary.php
+++ b/classes/output/navigation/primary.php
@@ -97,7 +97,6 @@ public function export_for_template(?renderer_base $output = null): array {
         }
 
         // Get the menus for the main menu.
-        $mainmenu = [];
         $mainmenu = smartmenu::get_menus_forlocation(smartmenu::LOCATION_MAIN, $smartmenus);
 
         // Convert the children menu items into submenus.