Add sample script for debugging during development

readme.md

@@ -41,3 +41,45 @@ We use [Composer](https://getcomposer.org) for managing PHP development dependen
 ## Screenshot
 
 ![Contact Form 7 Controls](screenshot-1.png)
+
+## Sample Analytics Scripts
+
+Note: all scripts use a fake account ID `abc123`.
+
+Google Tag Manager (GTM):
+
+```html
+<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
+new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
+j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
+'www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
+})(window,document,'script','dataLayer','GTM-abc123');</script>
+```
+
+Google Analytics 4 (gtag.js):
+
+```html
+<script async src="https://www.googletagmanager.com/gtag/js?id=G-abc123"></script>
+<script>
+  window.dataLayer = window.dataLayer || [];
+  function gtag(){dataLayer.push(arguments);}
+  gtag('js', new Date());
+  gtag('config', 'G-abc123');
+</script>
+```
+
+Facebook Pixel:
+
+```html
+<script>
+  !function(f,b,e,v,n,t,s)
+  {if(f.fbq)return;n=f.fbq=function(){n.callMethod?
+  n.callMethod.apply(n,arguments):n.queue.push(arguments)};
+  if(!f._fbq)f._fbq=n;n.push=n;n.loaded=!0;n.version='2.0';
+  n.queue=[];t=b.createElement(e);t.async=!0;
+  t.src=v;s=b.getElementsByTagName(e)[0];
+  s.parentNode.insertBefore(t,s)}(window, document,'script',
+  'https://connect.facebook.net/en_US/fbevents.js');
+  fbq('init', 'abc123');
+</script>
+```