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Twitter post by Daniel Feldman (@d_feldman): Linux is the only major operating system to support diagonal mode (credit [Twitter] @xssfox). Image shows an untrawide monitor rotated about 45 degrees, with a horizontal IDE window taking up a bottom triangle. A web browser and settings menu above it are organized creating a window shape almost like a stepped pyramid.
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I sort of agree with you to a degree, but I also think that the browser having knowledge of the size of your viewport actually has some use. Now, I would probably like it more if all webpages were just made with the restriction of not knowing the viewport size since that would dictate some design choices. Cellphones can just scroll around the page anyways. They should be second class citizens on the internet anyway in my opinion. The smartphone has been one of the worst inventions for the human race with how much it seems to isolate a lot of people more than connecting them.