diff --git a/gutenberg.php b/gutenberg.php
index e285a33310e81..4c811e8280772 100644
--- a/gutenberg.php
+++ b/gutenberg.php
@@ -164,7 +164,9 @@ function gutenberg_pre_init() {
 
 	require_once dirname( __FILE__ ) . '/lib/load.php';
 
-	gutenberg_silence_rest_errors();
+	if ( function_exists( 'gutenberg_silence_rest_errors' ) ) {
+		gutenberg_silence_rest_errors();
+	}
 
 	add_filter( 'replace_editor', 'gutenberg_init', 10, 2 );
 }