"No more vertical videos." - Joan Crawford's message for the digital generation.
Twitter's new snap-and-share video service, Vine, has forced users to break the first rule of iFilm making: never shoot vertical videos.
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Of course, Vine's videos appear as a square, so you could argue it doesn't really matter. But after years of comment shaming and PSAs to break novice video shooters of this deplorable habit, will Vine reverse all the progress made?
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This story originally published on Mashable here.