diff --git a/editor/assets/stylesheets/_z-index.scss b/editor/assets/stylesheets/_z-index.scss
index 50c4b1896453d1..cf98736f918ae7 100644
--- a/editor/assets/stylesheets/_z-index.scss
+++ b/editor/assets/stylesheets/_z-index.scss
@@ -13,8 +13,8 @@ $z-layers: (
 	'.editor-post-visibility__dialog': 30,
 	'.editor-post-schedule__dialog': 30,
 	'.editor-block-mover': 30,
-	'.components-notice-list': 100000,
-	'.components-popover': 100000,
+	'.components-notice-list': 9989, // Admin submenus (#adminmenu .wp-submenu) have z-index equal to 9999
+	'.components-popover': 9989, // Admin submenus (#adminmenu .wp-submenu) have z-index equal to 9999
 );
 
 @function z-index( $key ) {