Add info about what's happening to readme.md

Author: gregjacobs

README.md

@@ -11,3 +11,30 @@ You'll see two browser windows pop open:
 1. `http://localhost:8080` which has a broken page with errors in the console talking about how multiple copies of React have been loaded onto the page (React hooks error)
 2. `http://127.0.0.1:8888` which serves [webpack-bundle-analyzer](https://github.com/webpack-contrib/webpack-bundle-analyzer) showing the two separate copies of React files that have been loaded onto the page.
 
+![image](https://github.com/gregjacobs/rules-js-devserver-multiple-react-reproduction/assets/302273/0289219e-8993-43c9-a357-729147fffc85)
+
+## What's happening?
+
+Webpack is seeing two distinct `node_modules` directories because, in the `js_run_devserver` sandbox:
+
+1. _Unscoped_ (i.e. non '@org/*') node_modules are symlinked to:
+
+   `$(bazel info bazel-bin)/node_modules`
+
+2. _Scoped_ (i.e. '@org/*') node_modules are symlinked to:
+
+    `$(bazel info bazel-bin)/packages/app/serve.sh.runfiles/__main__/node_modules`
+
+**Unscoped packages:**
+
+![image](https://github.com/gregjacobs/rules-js-devserver-multiple-react-reproduction/assets/302273/c6d1e1a9-5706-49cc-ab6e-d1907abf27b0)
+
+**Scoped packages:**
+
+![image](https://github.com/gregjacobs/rules-js-devserver-multiple-react-reproduction/assets/302273/1a0e526d-2be0-4300-ae2e-f50d83aa4aad)
+
+And therefore it seems that transitive dependencies of the scoped `@my-org/button` package are also resolved under the runfiles node_modules directory, so we end up with:
+
+1. `$(bazel info bazel-bin)/node_modules/react` (from the Webpack app itself)
+2. `$(bazel info bazel-bin)/packages/app/serve.sh.runfiles/__main__/node_modules/react` (transitive dependency of the libary component used in the app)
+