B站多功能插件 is a free Chrome add-on developed by iae. This add-on is designed specifically for users of Bilibili, a popular Chinese video-sharing platform. It offers a range of useful features to enhance the Bilibili experience.

One of the key features of this add-on is the ability to adjust playback speed. With a simple keyboard shortcut, users can decrease or increase the playback speed by 0.5x. This can be useful for those who want to watch videos at a faster or slower pace.

Another useful feature is the ability to track and display the total duration of videos in a collection or series, as well as the remaining duration of unwatched videos. Users can easily see how much time they have left to finish a collection or series, providing a convenient way to manage their viewing.

Overall, B站多功能插件 is a handy add-on for Bilibili users who want to have more control over their video playback and keep track of their viewing progress. It's a free add-on that can be easily installed on the Chrome browser.