Watching web videos while you do other things on your desktop usually requires you to resize the browser window until it’s the size you want it to be. With Helium on Mac, it allows you to overlay web videos and look similar to the picture-in-picture mode of iOS 9. This can be used for videos from the likes of YouTube, Netflix, and all the other video streaming services online. To use Helium, you have to use Safari and install the necessary plugins. You can also drop the URL of a video into Helium and then it’ll play this for you.
Source: Helium | Via: Lifehacker