It looks like Twitter is testing a new feature to certain number of users.
The new feature is expected to provide users more space to add commentary when they are retweeting another user. The new feature, called”Retweet with Comment”, converts the retweeted message to an image and leaves users with the infamous 140-characters box for the comment.
This feature is the improvement of the previous one, where users need to click “Quote Tweet” if they wanted to add their own commentary to a retweet. This limitation has forced users to cram both the original tweet and the comment into 140-characters.
The experiments appeared to the mobile version and only tested to certain users. On the other hand, Twitter has not released the official statement about the implementation of this feature yet.