15 + Background Picture On Twitter High Quality Images. If you don't follow the standards, your images can appear skewed It's best to use a full-face photo on an uncluttered background. Nowadays they adapt this kinda thing where you can change zooms on the picture before uploading a new avatar.

21 + Background Picture On Twitter HD Wallpapers
Note that clicking one of these not only changes the background but also the color of the various parts and text of the page.
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