You should see no red rectangles or squares before or during the text
You should see a green square below
Click the
Go full screen
button below
The page should enter full screen mode, with only the green block being visible.
The browser might display a permission window asking you to allow full screen on this page. Allow it.
Exit full screen (e.g. by pressing
Esc
)
The green block should be visible, along with all the other initial content.
Go full screen
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