Merge pull request #3205 from Selectus2/fix/v6-upgrade-doc

v6 upgrade documentation fixed to get more understanding the use of j…

Author: guillaumebriday

docs/v6_upgrade.md

@@ -21,8 +21,8 @@ This means you have to configure integration with frameworks yourself, but webpa
     source_path: app/javascript
     source_entry_path: /
   ```
-  Then move your `app/javascript/packs/*` (including `application.js`) to `app/javascript/`. 
-  
+  Then move your `app/javascript/packs/*` (including `application.js`) to `app/javascript/`.
+
   Check if you had any entry point files in child directories of your `source_entry_path`. Files for entry points in child directories are not supported by rails/webpacker v6.
 
 2. Rename `config/webpack` to `config/webpack_old`
@@ -52,7 +52,7 @@ Example going to a specific version:
   bundle exec rails webpacker:install
   ```
 
-7. Update API usage of the view helpers by changing `javascript_packs_with_chunks_tag` and `stylesheet_packs_with_chunks_tag` to `javascript_pack_tag` and `stylesheet_pack_tag`. Ensure that your layouts and views will only have **at most one call** to `javascript_pack_tag` or `stylesheet_pack_tag`. You can now pass multiple bundles to these view helper methods. If you fail to changes this, you may experience performance issues, and other bugs related to multiple copies of React, like [issue 2932](https://github.com/rails/webpacker/issues/2932).  If you expose jquery globally with `expose-loader,` by using `import $ from "expose-loader?exposes=$,jQuery!jquery"` in your `app/javascript/application.js`, pass the option `defer: false` to your `javascript_pack_tag`.
+7. Update API usage of the view helpers by changing `javascript_packs_with_chunks_tag` and `stylesheet_packs_with_chunks_tag` to `javascript_pack_tag` and `stylesheet_pack_tag`. Ensure that your layouts and views will only have **at most one call** to `javascript_pack_tag` and **at most one call** to `stylesheet_pack_tag`. You can now pass multiple bundles to these view helper methods. If you fail to changes this, you may experience performance issues, and other bugs related to multiple copies of React, like [issue 2932](https://github.com/rails/webpacker/issues/2932).  If you expose jquery globally with `expose-loader,` by using `import $ from "expose-loader?exposes=$,jQuery!jquery"` in your `app/javascript/application.js`, pass the option `defer: false` to your `javascript_pack_tag`.
 8. If you are using any integrations like `css`, `React` or `TypeScript`. Please see https://github.com/rails/webpacker#integrations section on how they work in v6.
 9. Copy over any custom webpack config from `config/webpack_old`. Common code previously called 'environment' should be changed to 'base', and import `environment` changed to `webpackConfig`.