Please clarify if it's only on Disney+ that you're having the issue. Do other apps work well?
Also, isn't Disney+ of of the apps Comcast provides on that TV? That's one of the TVs using Comcast's XClass platform (similar to the Xfinity Flex platform), and Disney+ should be one of the apps available. So, if you launch the Disney+ app for your Comcast platform, does it experience the same issue?
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
If this post solves your problem please help others find this answer and click "Accept as Solution."
You may just be viewing content that was created in a format too wide to fit the 16:9 proportions of a standard wide screen tv. Many theatrical releases today are produced for theater screens that are wider than wide screen tvs.
In order to display the full content on the tv screen without cutting off the left and right edges of the image, these films are often "letterboxed", i.e. converted to the tv's 16:9 proprtions by adding black bars to the top and bottom of the image. The black bars are actually part of the image being sent to the Roku and so are sent on to your tv as received.
Your tv may have image controls that will allow you to zoom in far enough to eliminate the black bars but you'll cut off the parts at the edges that don't fit. One other option you may have is to keep the full width but stretch the image vertically to get rid of the bars, making the image abnormally tall and skinny. These settings would be on your tv, not your Roku.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
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