diff --git a/backend/tests/crawler_browser_smoke.rs b/backend/tests/crawler_browser_smoke.rs
index b2df9cf..ac74f60 100644
--- a/backend/tests/crawler_browser_smoke.rs
+++ b/backend/tests/crawler_browser_smoke.rs
@@ -113,6 +113,7 @@ async fn extra_args_reach_chromium() {
     let options = LaunchOptions {
         mode: browser::BrowserMode::Headless,
         extra_args: vec![format!("--user-agent={UA}")],
+        user_agent: None,
     };
     let handle = browser::launch(options).await.expect("launch with extra args");