Intermittent timeout in /websockets/constructor/016.html

```

  ▶ TIMEOUT [expected OK] /websockets/constructor/016.html
  │ 
  └ Xlib:  extension "XFree86-VidModeExtension" missing on display ":0".

  ▶ Unexpected subtest result in /websockets/constructor/016.html:
  │ TIMEOUT [expected FAIL] WebSockets: non-ascii URL in query, document encoding windows-1252
  └   → Test timed out
```
