diff --git a/src/wp-admin/css/customize-controls.css b/src/wp-admin/css/customize-controls.css
index 8dacce89cb..86e5fb5ff6 100644
--- a/src/wp-admin/css/customize-controls.css
+++ b/src/wp-admin/css/customize-controls.css
@@ -132,7 +132,7 @@ body {
 }
 
 #customize-theme-controls .control-section:last-of-type.open,
-#customize-theme-controls .control-section:last-of-type .accordion-section-title {
+#customize-theme-controls .control-section:last-of-type > .accordion-section-title {
 	border-bottom-color: #ddd;
 }
 
diff --git a/src/wp-admin/customize.php b/src/wp-admin/customize.php
index b5524b00e7..de43197695 100644
--- a/src/wp-admin/customize.php
+++ b/src/wp-admin/customize.php
@@ -161,11 +161,8 @@ do_action( 'customize_controls_print_scripts' );
 
 			<div id="customize-theme-controls"><ul>
 				<?php
-				foreach ( $wp_customize->panels() as $panel ) {
-					$panel->maybe_render();
-				}
-				foreach ( $wp_customize->sections() as $section ) {
-					$section->maybe_render();
+				foreach ( $wp_customize->containers() as $container ) {
+					$container->maybe_render();
 				}
 				?>
 			</ul></div>
diff --git a/src/wp-includes/class-wp-customize-manager.php b/src/wp-includes/class-wp-customize-manager.php
index 6a04ea7a12..4465a80545 100644
--- a/src/wp-includes/class-wp-customize-manager.php
+++ b/src/wp-includes/class-wp-customize-manager.php
@@ -43,10 +43,11 @@ final class WP_Customize_Manager {
 	 */
 	public $widgets;
 
-	protected $settings = array();
-	protected $panels   = array();
-	protected $sections = array();
-	protected $controls = array();
+	protected $settings   = array();
+	protected $containers = array();
+	protected $panels     = array();
+	protected $sections   = array();
+	protected $controls   = array();
 
 	protected $nonce_tick;
 
@@ -305,6 +306,17 @@ final class WP_Customize_Manager {
 		return $this->controls;
 	}
 
+	/**
+	 * Get the registered containers.
+	 *
+	 * @since 4.0.0
+	 *
+	 * @return array
+	 */
+	public function containers() {
+		return $this->containers;
+	}
+
 	/**
 	 * Get the registered sections.
 	 *
@@ -891,6 +903,10 @@ final class WP_Customize_Manager {
 			$panels[] = $panel;
 		}
 		$this->panels = $panels;
+
+		// Sort panels and top-level sections together.
+		$this->containers = array_merge( $this->panels, $this->sections );
+		uasort( $this->containers, array( $this, '_cmp_priority' ) );
 	}
 
 	/**
diff --git a/src/wp-includes/class-wp-customize-widgets.php b/src/wp-includes/class-wp-customize-widgets.php
index 3634dabbf0..4413ee6b9d 100644
--- a/src/wp-includes/class-wp-customize-widgets.php
+++ b/src/wp-includes/class-wp-customize-widgets.php
@@ -434,8 +434,9 @@ final class WP_Customize_Widgets {
 		}
 
 		$this->manager->add_panel( 'widgets', array(
-			'title' => __( 'Widgets' ),
+			'title'       => __( 'Widgets' ),
 			'description' => __( 'Widgets are independent sections of content that can be placed into widgetized areas provided by your theme (commonly called sidebars).' ),
+			'priority'    => 110,
 		) );
 
 		foreach ( $sidebars_widgets as $sidebar_id => $sidebar_widget_ids ) {