This is not mentioned in the article, so just to be more specific, the override of `XMLHttpRequest.open()` applies only for the Safari-specific code of the extension.[1]<p>[1] See <a href="https:&#x2F;&#x2F;github.com&#x2F;chrisaljoudi&#x2F;uBlock&#x2F;tree&#x2F;master&#x2F;platform&#x2F;safari#" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;chrisaljoudi&#x2F;uBlock&#x2F;tree&#x2F;master&#x2F;platform&#x2F;...</a>, the code is in `vapi-client.js`, line 247.