I appreciate your reply. With that said, Roku needs to officially chime in here and explain this.
The problem is Rumble-wide, not a specific channel on Rumble. It exists on both Rumble and RumbleTV apps (doesn't seem to be a difference between the 2 apps in any way).
It just started a few weeks ago, with nothing changing, such as doing updates.
The problem isn't with the TV. As I stated, Rumble is the only app on Roku that does this. And, no other source to my TV does it. My TV isn't a political spin-doctor. And even if it was, it doesn't possess the capability to express bias against one channel, and let others display correctly.
Both Rumble apps are up to date, 6/30/21, according to Roku.
My Roku display settings are set to 4:3, which is appropriate for my TV.
As you can see in the pic below, it only displays the upper left corner of the entire app, not just the video that I select on a specific channel.
The problem actually starts while the app is loading. The "Rumble" logo, which is supposed to be centered, displays "Rumb" on screen, like it's trying to display in 16:9. Once it loads, it only displays my list of channels and about 80% of the left-most episode, regardless of which channel I highlight. I can't see the text under each episode that shows the date, so I have to find it on my computer, and match it to the picture. Once I select an episode to watch, the display actually gets much better. It plays almost the full extent left-right, and only seems to clip off the bottom, so I can't see the slider bar.