Hopefully this benefits others with the same problem.
Displaying your Twitter tweets on your Google Sites website is difficult!
Google Sites filters your HTML code and doesn't allow you to add your own JavaScript code, therefore restricting you from adding any of the many existing Twitter widgets that exist today, including Twitter's very own.
The Google Gadgets directory contains a Twitter gadget called Twit. This is the gadget I was using in the past.
It uses http
but Google Sites uses https
, therefore this gadget is considered as insecure content and is not displayed by default on certain browsers (e.g. Chrome browser). Instead the user is asked if they want to display insecure content and are recommended not to. Now your visitors will think your site hosts malicious content and they can't easily read your tweets.