YouTube Auto HD FPS is a Firefox extension designed to enhance the video quality settings for YouTube users. This tool allows users to customize their viewing experience by adjusting video quality from 144p to 8K based on the video's frames per second (FPS). It supports various resolution settings, enabling users to select higher quality options for 30FPS and 60FPS videos, making it versatile for different types of content.

In addition to quality adjustments, the extension offers an automatic bitrate selection feature that optimizes the video playback experience. Users can also set the quality for embedded videos outside of YouTube.com, ensuring a consistent viewing experience across different platforms. The auto-resize feature further enhances usability by automatically adjusting the video size to fit the viewer's preferences.