The widget currently covers approximately 86% of browsers in use today, and you can see the list here.
In the event that a user browsing your website uses a different browser, the widget will simply emit no HTML, and hence you should plan to handle this scenario gracefully.
The widget automatically includes the necessary polyfills to support the above in its bundle.
The widget occasionally emits minimal logging in to the browser's console log. If a required parameter is either not passed or incorrect, an error will be logged to the console. If an optional parameter is incorrect, a warning will be logged to the console.