Simple Twitch Viewer is a Chrome extension that allows you to enlarge Twitch videos without changing the window size. With this extension, you can apply Twitch's theater mode by reducing the window size and then clicking on the Simple Twitch Viewer icon. By moving the chat box to the bottom and minimizing the margins, you can enjoy larger video playback without altering the window size.

This extension is designed to accommodate Twitch's specification changes, ensuring compatibility with the latest updates. It also supports manifest_version 3, allowing it to continue functioning beyond 2023.

Please note that Simple Twitch Viewer also offers the option to remove the header at the top of the comment section, providing a cleaner viewing experience.