由于不能科学的上网。网上看资料装上了这个插件，装的过程有点坑。记录一下，希望能帮到和我一样的新手。
1.第一步，克隆下远程仓库的东西。
桌面右键，git-bash。然后输入：
git clone https://github.com/facebook/react-devtools.git
这个过程耗时比较长。
结果：
2.第二步， 进入到react-devtools目录，安装依赖
cd react-devtools npm install
过程耗时长。安装碰上的情况。如下：
admin@battle MINGW64 ~/Desktop
$ cd react-devtools
admin@battle MINGW64 ~/Desktop/react-devtools (master)
$ npm install
npm WARN deprecated clipboard-js@0.3.6: Please migrate to https://github.com/lgarron/clipboard-polyfill
npm WARN deprecated core-js@1.2.7: core-js@<2.6.8 is no longer maintained. Please, upgrade to core-js@3 or at least to actual version of core-js@2.
npm WARN deprecated gulp-util@3.0.8: gulp-util is deprecated - replace it, following the guidelines at https://medium.com/gulpjs/gulp-util-ca3b1f9f9ac5
npm WARN deprecated cross-spawn-async@2.2.5: cross-spawn no longer requires a build toolchain, use it instead
npm WARN deprecated firefox-client@0.3.0: Package no longer supported. Contact support@npmjs.com for more info.
npm WARN deprecated circular-json@0.3.3: CircularJSON is in maintenance only, flatted is its successor.
npm WARN deprecated js-select@0.6.0: Package no longer supported. Contact support@npmjs.com for more info.
npm WARN deprecated hawk@3.1.3: This module moved to @hapi/hawk. Please make sure to switch over as this distribution is no longer supported and may contain bugs and critical security issues.
npm WARN deprecated left-pad@1.3.0: use String.prototype.padStart()
npm WARN deprecated joi@6.10.1: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).
npm WARN deprecated sntp@1.0.9: This module moved to @hapi/sntp. Please make sure to switch over as this distribution is no longer supported and may contain bugs and critical security issues.
npm WARN deprecated cryptiles@2.0.5: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).
npm WARN deprecated topo@1.1.0: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).
npm WARN deprecated hoek@2.16.3: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).
npm WARN deprecated boom@2.10.1: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).
> dtrace-provider@0.8.7 install C:\Users\admin\Desktop\react-devtools\node_modules\dtrace-provider
> node-gyp rebuild || node suppress-error.js
C:\Users\admin\Desktop\react-devtools\node_modules\dtrace-provider>if not defined npm_config_node_gyp (node "C:\Program Files\nodejs\node_modules\npm\node_modules\npm-lifecycle\node-gyp-bin\\..\..\node_modules\node-gyp\bin\node-gyp.js" rebuild ) else (node "C:\Program Files\nodejs\node_modules\npm\node_modules\node-gyp\bin\node-gyp.js" rebuild )
gyp ERR! configure error
gyp ERR! stack Error: Can't find Python executable "python", you can set the PYTHON env variable.
gyp ERR! stack at PythonFinder.failNoPython (C:\Program Files\nodejs\node_modules\npm\node_modules\node-gyp\lib\configure.js:484:19)
gyp ERR! stack at PythonFinder.<anonymous> (C:\Program Files\nodejs\node_modules\npm\node_modules\node-gyp\lib\configure.js:509:16)
gyp ERR! stack at C:\Program Files\nodejs\node_modules\npm\node_modules\graceful-fs\polyfills.js:284:29
gyp ERR! stack at FSReqWrap.oncomplete (fs.js:153:21)
gyp ERR! System Windows_NT 10.0.17134
gyp ERR! command "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\node_modules\\node-gyp\\bin\\node-gyp.js" "rebuild"
gyp ERR! cwd C:\Users\admin\Desktop\react-devtools\node_modules\dtrace-provider
gyp ERR! node -v v10.15.3
gyp ERR! node-gyp -v v3.8.0
gyp ERR! not ok
> command-join@2.0.1 postinstall C:\Users\admin\Desktop\react-devtools\node_modules\command-join
> npx -p @seangenabe/tnx tnx || exit 0
npx: 1 安装成功，用时 3.104 秒
Thanks for installing command-join!
If you like this package, be sure to star its repo,
and please consider donating:
https://seangenabe.netlify.com/donate
> core-js@2.6.9 postinstall C:\Users\admin\Desktop\react-devtools\node_modules\core-js
> node scripts/postinstall || echo "ignore"
Thank you for using core-js ( https://github.com/zloirock/core-js ) for polyfilling JavaScript standard library!
The project needs your help! Please consider supporting of core-js on Open Collective or Patreon:
> https://opencollective.com/core-js
> https://www.patreon.com/zloirock
Also, the author of core-js ( https://github.com/zloirock ) is looking for a good job -)
> core-js-pure@3.1.4 postinstall C:\Users\admin\Desktop\react-devtools\node_modules\core-js-pure
> node scripts/postinstall || echo "ignore"
Thank you for using core-js ( https://github.com/zloirock/core-js ) for polyfilling JavaScript standard library!
The project needs your help! Please consider supporting of core-js on Open Collective or Patreon:
> https://opencollective.com/core-js
> https://www.patreon.com/zloirock
Also, the author of core-js ( https://github.com/zloirock ) is looking for a good job -)
> spawn-sync@1.0.15 postinstall C:\Users\admin\Desktop\react-devtools\node_modules\spawn-sync
> node postinstall
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN ajv-errors@1.0.1 requires a peer of ajv@>=5.0.0 but none is installed. You must install peer dependencies yourself.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.9 (node_modules\fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.9: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})
added 1781 packages from 819 contributors and audited 32379 packages in 131.133s
found 76 vulnerabilities (66 low, 7 moderate, 2 high, 1 critical)
run `npm audit fix` to fix them, or `npm audit` for details
直接忽略了。。继续下一步。
3.打包一份扩展程序。如下：
npm run build:extension:chrome
结果：
这个时候就可以在react-devtools目录下找到shells--chrome--build--unpacked文件夹。
4.打开chrome，地址栏输出：chrome://extensions/。 左上角点击加载已解压的扩展程序。把unpacked文件夹放进去了。
大功告成，右上角多了个react图标。