SiteBuilder websites are supported by all practically all web browsers. Different web browsers have different limitations for functions and features, it is important to keep your web browser up to date to ensure you are making the most of the modern web.
For example, Microsoft Internet Explorer (IE) 7 and 8 do not support element rotation and roundness. This means any elements with round corners will not show this way on IE7 or 8, Microsoft don't support these older versions anymore so not only from a visual point of view, but also from a security stand point, we highly recommend updating.