To upload a video on the Twitter PWA, all you need to do is compose a tweet, then click the insert media icon on the left. You can then select your video file, and get a small preview of the video below the compose box. Interestingly, this preview video uses the same media player UI as Windows Phone 8.
Additionally, as the name of the second feature implies, you can now hover your mouse over the name of a profile to see a preview of the profile. The pop-up box will show you the bio, the number of followers, and the number of people the person is following.
Support for video uploads has been one of the most anticipated features for the Twitter PWA, but it does seem to be a bit buggy at the moment. Anyway, you won’t need to download any updates for this to work, as all PWAs are updated automatically. Check it out now, and let us know in the comments below if it is working for you.