get rid of polyfill since this is just chrome anyway.

extension/prompt.jsx

@@ -1,4 +1,3 @@
-import browser from 'webextension-polyfill'
 import {render} from 'react-dom'
 import React from 'react'
 
@@ -72,7 +71,7 @@ function Prompt() {
   function authorizeHandler(condition) {
     return function (ev) {
       ev.preventDefault()
-      browser.runtime.sendMessage({
+      chrome.runtime.sendMessage({
         prompt: true,
         id,
         host,