You do not have permission to use blocking webRequest listeners. Be sure to declare the webRequestBlocking permission in your manifest

我试图用react js开发我的第一个chrome扩展。当我试图在chrome扩展中使用chrome.webRequest API封锁一个URL时，在错误页面显示了两个错误。

'webRequestBlocking' requires manifest version of 2 or lower.

Unchecked runtime.lastError: You do not have permission to use blocking webRequest listeners. Be sure to declare the webRequestBlocking permission in your manifest.

我在清单文件中声明了"webRequestBlocking"权限。以下是我的清单.json

{
  "manifest_version": 3,
  "name": "Chrome Extension",
  "description": "First Extension",
  "options_page": "options.html",
  "background": {
  "service_worker": "background.bundle.js",
  "matches": [
   "<all_urls>"
  ]
},
 "action": {
 "default_title": "Open Extension",
 "default_icon": "icon-34.png"
 },
 "icons": {
 "128": "icon-128.png"
 },
 "content_scripts": [
 {
   "matches": [
    "http://*/*",
    "https://*/*",
    "<all_urls>"
   ],
   "js": [
    "contentScript.bundle.js"
   ],
   "css": [
    "content.styles.css"
   ]
  }
 ],
 "devtools_page": "devtools.html",
 "web_accessible_resources": [
 {
  "resources": [
    "content.styles.css",
    "icon-128.png",
    "icon-34.png"
   ],
   "matches": []
  }
 ],
  "permissions": [
  "activeTab",
  "tabs",
  "webRequest",
  "webRequestBlocking"
 ],
 "host_permissions": [
  "<all_urls>"
 ]
}

这是我的background.js

chrome.webRequest.onBeforeRequest.addListener(
  function(details) {
    console.log(details);
    return {cancel: true};
  },
  {urls: ["https://reactjs.org/"]},
  ["blocking"]
);

我试着去掉了webRequestBlocking，但也是一样的。谁能帮帮我，有什么办法能解决这个问题吗？

该错误解释了它自己 'webRequestBlocking' requires manifest version of 2 or lower. 所以你不能在manifest 3中使用webRequestBlocking 。

但chrome给出了一个替代方案，即使用declarativeNetRequestWithHostAccess API witch，通过指定声明性规则来阻止或修改网络请求，你可以查看这里以了解更多细节。

你可以把manifest_version改成2，把webRequestBlocking改成permissions。