Roly, Xara's preview is to a local web server, like http://localhost:8000/virtnnnnnnnn/index.htm so when you view it in IE or Chrome or Firefox or Edge or Safari or Opera, you get the experience of it being on the Internet except the download speeds are not around.
And the power of xara's solution is they rendering is almost the same across all these browsers, IE usually being off key the most.
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