diff --git a/codejar.ts b/codejar.ts
index 4d6a8b3..da695da 100644
--- a/codejar.ts
+++ b/codejar.ts
@@ -464,8 +464,8 @@ export function CodeJar(editor: HTMLElement, highlight: (e: HTMLElement, pos?: P
   }
 
   return {
-    updateOptions(options: Partial<Options>) {
-      options = {...options, ...options}
+    updateOptions(newOptions: Partial<Options>) {
+      Object.assign(options, newOptions)
     },
     updateCode(code: string) {
       editor.textContent = code