BigTube is a Chrome add-on developed by Pregnantboy that enhances your YouTube viewing experience. This free program offers a full-sized theater mode, a miniplayer on scroll, and a popout player for all video sites.

With BigTube, you can maximize your browser real estate by fully expanding the YouTube video player without going into fullscreen mode. This allows you to watch videos with a larger player while still having access to your browser's other features.

The add-on also provides various fixes and updates to ensure compatibility with YouTube's new styling. In addition, it introduces new features like the miniplayer on scroll, which allows you to read comments while still watching the video.

Overall, BigTube is a useful tool for YouTube enthusiasts who want to enhance their viewing experience and make the most out of their browser space.