After announcing picture-heavy web profiles for all users, Twitter is looking to bring quicker engagement. Twitter announced that users who access Twitter.com will receive pop-up notifications when others on the platform engage with them (retweets, mentions or direct messages) This notification will appear in the lower-right hand corner of the timeline.
This is enrolled because Twitter wants to make the service more interactive & engaging, so you’ll be able to reply or follow somebody back from the pop-up notification box, which will appear in the right-hand corner of Twitter.com. You can choose which alerts they want to be notified for. The notification settings will be available within the general settings page.
Speaking of this also make me think that Twitter is taking inspiration from many Facebook features. The web profiles down to the cover image and now the real-time notifications which are also something Facebook introduced a while back.