Twitter testing new Facebook-style layout
Select users are reporting that their Twitter profiles look now look like the image above, complete with large header photos (up to 1500 x 1500 pixels), left-aligned square profile images and flat content cards representing each tweet.
The new design is also allowing users to “Pin this Tweet” to the top of your profile page. See this video below:
The changes are just in the testing phase, but expect some of these changes to be rolled out to all users soon.