docs: add more guide (#39117)

* docs: add more guide

* docs: add webpack plugin

docs/react/migration-v5.en-US.md

@@ -203,10 +203,45 @@ Umi user can disable by config：
 export default {
   antd: {
 -   import: true,
++   import: false,
   },
 };
 ```
 
+### Replace Day.js locale
+
+Replace moment.js locale with day.js locale:
+
+```diff
+-   import moment from 'moment';
++   import dayjs from 'dayjs';
+-   import 'moment/locale/zh-cn';
++   import 'dayjs/locale/zh-cn';
+
+-   moment.locale('zh-cn');
++   dayjs.locale('zh-cn');
+```
+
+If you do not want to replace with day.js, you can use `@ant-design/moment-webpack-plugin` to keep moment.js:
+
+```bash
+npm install --save-dev @ant-design/moment-webpack-plugin
+```
+
+```javascript
+// webpack-config.js
+import AntdMomentWebpackPlugin from '@ant-design/moment-webpack-plugin';
+
+module.exports = {
+  // ...
+  plugins: [new AntdMomentWebpackPlugin()],
+};
+```
+
+### Legacy browser support
+
+Ant Design v5 using `:where` css selector to reduce CSS-in-JS hash priority. You can use `@ant-design/cssinjs` `StyleProvider` to cancel this function. Please ref [Compatible adjustment](/docs/react/customize-theme#compatible-adjustment).
+
 ## Encounter problems
 
 If you encounter problems during the upgrade, please go to [GitHub issues](https://new-issue.ant.design/) for feedback. We will respond and improve this document as soon as possible.

docs/react/migration-v5.zh-CN.md

@@ -197,10 +197,45 @@ Umi 用户可以在配置文件中关闭：
 export default {
   antd: {
 -   import: true,
++   import: false,
   },
 };
 ```
 
+### 替换 Day.js 语言包
+
+将 moment.js 的 locale 替换为 day.js 的 locale 引入：
+
+```diff
+-   import moment from 'moment';
++   import dayjs from 'dayjs';
+-   import 'moment/locale/zh-cn';
++   import 'dayjs/locale/zh-cn';
+
+-   moment.locale('zh-cn');
++   dayjs.locale('zh-cn');
+```
+
+如果你暂时不想替换 day.js，也可以使用 `@ant-design/moment-webpack-plugin` 插件将 day.js 替换回 moment.js：
+
+```bash
+npm install --save-dev @ant-design/moment-webpack-plugin
+```
+
+```javascript
+// webpack-config.js
+import AntdMomentWebpackPlugin from '@ant-design/moment-webpack-plugin';
+
+module.exports = {
+  // ...
+  plugins: [new AntdMomentWebpackPlugin()],
+};
+```
+
+### 旧版浏览器兼容
+
+Ant Design v5 使用 `:where` css selector 降低 CSS-in-JS hash 值优先级，如果你需要支持旧版本浏览器（如 IE 11、360 浏览器 等等）。可以通过 `@ant-design/cssinjs` 的 `StyleProvider` 去除降权操作。详情请参阅 [兼容性调整](/docs/react/customize-theme-cn#兼容性调整)。
+
 ## 遇到问题
 
 如果您在升级过程中遇到了问题，请到 [GitHub issues](https://new-issue.ant.design/) 进行反馈。我们会尽快响应和相应改进这篇文档。