const extension = require('extensionizer') var port = extension.runtime.connect({name: 'blacklister'}) port.postMessage({ 'pageLoaded': window.location.hostname }) port.onMessage.addListener(redirectIfBlacklisted) function redirectIfBlacklisted (response) { const { blacklist } = response const host = window.location.hostname if (blacklist && blacklist === host) { window.location.href = 'https://metamask.io/phishing.html' } }