[#106] Update README (#107)

Author: marco-prontera

README.md

@@ -11,6 +11,10 @@ Essentially what it does is take all the CSS generated by the build process and
 therefore not generated and the declaration in the generated HTML file is also removed. You can also configure when the
 CSS injection will be executed (before or after your app code).
 
+### A note for plugin-legacy users
+At first the plugin supported generating the CSS injection code also in the legacy files generated by the [plugin-legacy](https://github.com/vitejs/vite/tree/main/packages/plugin-legacy). Since the plugin-legacy injects the CSS code for [different reasons](https://github.com/vitejs/vite/issues/2062), this plugin no longer has the plugin-legacy support code. 
+If the code of the plugin-legacy changes an update to this plugin may occur.
+
 ## Installation
 
 ```
@@ -240,7 +244,7 @@ export default {
 
 #### relativeCSSInjection (boolean)
 
-**!!! Experimental feature !!!**
+_This feature is based on information provided by Vite. Since we can't control how Vite handles this information this means that there may be problems that may not be possible to fix them in this plugin._
 
 The default behavior of this plugin takes all the CSS code of your application directly to the entrypoint generated.
 The `relativeCSSInjection` if configured to `true` will inject the CSS code of every entrypoint to the relative importer.