In September, Twitter rolled out a redesign to its users profile pages that featured header photos.
The Facebook (FB)-like update has far been optional for users, but starting Wednesday the social network all require all users to adopt the new design,the company said on its blog.
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"On December 12, we're rolling this out to all users: you'll automatically get this new version of the profile on twitter.com. If you don't upload a header photo by then, you (and everyone else) will only see a default grey image on your page. That's not fun!" the company said.
If you're not sure how to upload a header photo on your Twitter page, the social network has a how-to video that breaks the process down.
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