Thank you for the feedback! You are correct, the new twitter UI requires you to be "focused" on the twitter tab for it to load new tweets. I'm not sure why they do that. I personally don't like the new UI but that's a different story.

What's interesting is that you are still able to use the old version of twitter. I honestly thought it was gone for good for all users, which is why I updated the add-on to support the new version only.

Based on this, I will try to find a way of detecting what version of twitter you are using, and make the add-on behave differently based on that.

Again thanks for the feedback!

Edit: The new version that supports the old and new design is up, can you let me know if it works? thanks!