Just imagine, you use sitespeed to monitor your website , and your website throws a javascript alert popup – this will usually throw some error. To fix this issue, you can try this script:
module.exports = async function(context, commands) {
// Measure the page and give it the alias StartPage
const driver = context.selenium.driver;
const webdriver = context.selenium.webdriver;
await commands.measure.start();
await driver.get('http://www.yoururl.com');
await driver.switchTo().alert().accept();
await commands.measure.stop();
};