It only gives access to "On Demand" and not live channels. You need the app for Windows 10.
The XFINITY TV portal (https://tv.xfinity.com) allows you to watch your full channel lineup while connected to your in-home XFINITY network and over 190 channels from anywhere in the USA. Please select the "Available out of home" filter in the "Live TV" section to show just the "TV Go" live TV channels.
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