You may find with the S20 Ultra that you can not post of Facebook because the option is gone. You may also fine when you touch the three lines to pull up saved videos and other options such as getting to your page, the screen won't let you pull it down all the way to show the tabs. They will be cut off or just not there. I figured out the issue with this. Go into the settings in the phone. In the display option. Go to Full Screen Apps. Then go to the app you are having trouble viewing in full screen (Facebook in my case) and turn the off (Auto) for the app set it set to (Full screen). This immediately fixed the problem with not being able to pull the screen down to make a post in the Facebook app.
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