View Thumbnail is a Chrome add-on developed by sglee487. It is a free program that falls under the Browsers category, specifically the Add-ons & Tools subcategory. The main purpose of this add-on is to provide a convenient way to view the thumbnail of a YouTube video that is currently playing.

With View Thumbnail, users can easily see the thumbnail of the video they are watching on YouTube in a popup window. This eliminates the need to pause the video or open a new tab to view the thumbnail. The add-on seamlessly integrates into the Chrome browser, allowing for a smooth and efficient user experience.

By simply hovering over the video player, the thumbnail will appear in a small popup window, providing a quick glimpse of what the video is about. This feature can be particularly useful for users who want to quickly check the content of a video without interrupting their viewing experience.

Overall, View Thumbnail is a useful add-on for YouTube enthusiasts who want to easily view the thumbnail of a video while it is playing. It offers a simple and convenient solution that enhances the YouTube browsing experience.