diff --git a/wp-includes/comment-template.php b/wp-includes/comment-template.php
index f71d61284f..06e897912b 100644
--- a/wp-includes/comment-template.php
+++ b/wp-includes/comment-template.php
@@ -2480,7 +2480,7 @@ function comment_form( $args = array(), $post_id = null ) {
 	 */
 	$args = wp_parse_args( $args, apply_filters( 'comment_form_defaults', $defaults ) );
 
-	// Ensure that the filtered args contain all required default values.
+	// Ensure that the filtered arguments contain all required default values.
 	$args = array_merge( $defaults, $args );
 
 	// Remove `aria-describedby` from the email field if there's no associated description.
diff --git a/wp-includes/general-template.php b/wp-includes/general-template.php
index ec9eba3e93..b334e5a862 100644
--- a/wp-includes/general-template.php
+++ b/wp-includes/general-template.php
@@ -281,6 +281,9 @@ function get_search_form( $args = array() ) {
 	 */
 	$args = apply_filters( 'search_form_args', $args );
 
+	// Ensure that the filtered arguments contain all required default values.
+	$args = array_merge( $defaults, $args );
+
 	$format = current_theme_supports( 'html5', 'search-form' ) ? 'html5' : 'xhtml';
 
 	/**
@@ -303,7 +306,7 @@ function get_search_form( $args = array() ) {
 		$form = ob_get_clean();
 	} else {
 		// Build a string containing an aria-label to use for the search form.
-		if ( isset( $args['aria_label'] ) && $args['aria_label'] ) {
+		if ( $args['aria_label'] ) {
 			$aria_label = 'aria-label="' . esc_attr( $args['aria_label'] ) . '" ';
 		} else {
 			/*
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 5dc3ba76ce..dae116c3c2 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.5.2-alpha-49340';
+$wp_version = '5.5.2-alpha-49356';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.