Update Example Based on loadCSS Best Practice

README.md

@@ -27,7 +27,7 @@ The loadCSS and onloadCSS files will be added to the asset pipeline and availabl
 Here's a quick example of what you would drop in your application's layout (usually `app/views/layouts/application.html.erb`):
 
 ```html
-<link rel="preload" href="<%= stylesheet_path('application') %>" as="style" onload="this.rel='stylesheet'">
+<link rel="preload" href="<%= stylesheet_path('application') %>" as="style" onload="this.onload=null;this.rel='stylesheet'">
 <noscript><link rel="stylesheet" href="<%= stylesheet_path('application') %>"></noscript>
 ```
 
@@ -50,4 +50,4 @@ Feel free to open an issue ticket if you find something that could be improved.
 
 * If the loadCSS scripts are outdated (i.e. maybe a new version of loadCSS was released yesterday), feel free to open an issue and prod us to get that thing updated. However, for security reasons, we won't be accepting pull requests with updated loadCSS scripts.
 
-Copyright Michael Misshore, released under the MIT License.
+Copyright Michael Misshore, released under the MIT License.