diff --git a/wp-admin/load-styles.php b/wp-admin/load-styles.php
index d2f8bfbdee..c51355d720 100644
--- a/wp-admin/load-styles.php
+++ b/wp-admin/load-styles.php
@@ -117,13 +117,13 @@ foreach( $load as $handle ) {
 	$style = $wp_styles->registered[$handle];
 	$path = ABSPATH . $style->src;
 
-	$content = get_file($path) . "\n";
-
-	if ( $rtl && isset($style->extra['rtl']) && $style->extra['rtl'] ) {
-		$rtl_path = is_bool($style->extra['rtl']) ? str_replace( '.min.css', '-rtl.min.css', $path ) : ABSPATH . $style->extra['rtl'];
-		$content .= get_file($rtl_path) . "\n";
+	if ( $rtl && ! empty( $style->extra['rtl'] ) ) {
+		// All default styles have fully independent RTL files.
+		$path = str_replace( '.min.css', '-rtl.min.css', $path );
 	}
 
+	$content = get_file( $path ) . "\n";
+
 	if ( strpos( $style->src, '/wp-includes/css/' ) === 0 ) {
 		$content = str_replace( '../images/', '../wp-includes/images/', $content );
 		$out .= str_replace( '../js/tinymce/', '../wp-includes/js/tinymce/', $content );
diff --git a/wp-includes/script-loader.php b/wp-includes/script-loader.php
index a22e3888e5..76da68b4b8 100644
--- a/wp-includes/script-loader.php
+++ b/wp-includes/script-loader.php
@@ -591,6 +591,9 @@ function wp_default_styles( &$styles ) {
 
 	foreach ( $rtl_styles as $rtl_style ) {
 		$styles->add_data( $rtl_style, 'rtl', 'replace' );
+		if ( $suffix ) {
+			$styles->add_data( $rtl_style, 'suffix', $suffix );
+		}
 	}
 }