Is it possible to disable this thing in the lower left corner for screenshots?
Just press F9 and UE4 will take a screenshot of the active viewport and place it in your project’s saved folder.
This is the only interface element that is saved in the image when you take a screenshot via F9.
Or it can be turned off in some settings or it can be a watermark of protection.
Since i had the same issue. Press on the top left of the editor window the small triangle to open the menu and tick GameView option, or press “G” for that. This way your viewport will look like it would when running the game.