Thanks for your patience. Replace the url of this page in your code with securly-vulnerability-tester.99885681.xyz to continue testing this issue. If you need the code for testing, scroll (first is bookmarklet, then google apps script, then devtools console code):
javascript:(function(){var u=prompt('URL:','https://example.com');if(!u)return;function p(x){var d=document;d.open();d.write('');d.close()}p(u)})()