zh-downloader is a free Chrome add-on developed by shellvon. It falls under the category of browsers and subcategory of Add-ons & Tools. This add-on automatically detects Zhihu video resources and allows users to download and save them directly.

To use zh-downloader, simply open a Zhihu webpage and the add-on will automatically detect the corresponding video resources for users to manipulate. Users have the option to download videos in different resolutions and can also share videos with friends or on social media platforms.

With zh-downloader, users can easily save Zhihu videos for offline viewing or sharing purposes. It provides a convenient way for Zhihu users to access and download video content without the need for external tools or complicated processes.