Update banner instructions

Author: marcprux

src/content/pages/banner.md

@@ -13,6 +13,7 @@ Inserts a full-width banner at the top of the page:
 ```html
 <script src="https://keepandroidopen.org/banner.js"></script>
 ```
+<script src="/banner.js"></script>
 
 ## Query parameters
 
@@ -28,14 +29,6 @@ Customize the banner by appending query parameters to the script URL:
 
 ## Examples
 
-Basic usage, displays at the top of the page:
-
-```html
-<script src="https://keepandroidopen.org/banner.js"></script>
-```
-
-<script src="/banner.js"></script>
-
 French, mini size, inserted into a specific element:
 
 ```html
@@ -53,6 +46,10 @@ Link to a custom page, no close button:
 <script src="https://keepandroidopen.org/banner.js?link=https://example.com/android&hidebutton=off"></script>
 ```
 
+## Source
+
+The source for the banner can be found at [https://github.com/keepandroidopen/keepandroidopen.github.io/blob/main/public/banner.js](https://github.com/keepandroidopen/keepandroidopen.github.io/blob/main/public/banner.js). Suggestions for improvement are welcome!
+
 <div id="my-banner-custom"></div>
 <script src="/banner.js?link=https://example.com/android&hidebutton=off&size=mini&id=my-banner-custom"></script>