On desktop Google Chrome, this feature has been promised to us last year in the form of a Picture-in-Picture Web API specification. This is speculative to allow websites to initiate and control PiP behaviour. We found evidence that the feature was on its way to desktop Google Chrome soon, and now, the feature is finally available. You do need Chrome 68 or beyond for this extension to work, and you also need the extension, obviously. Kasik96 has shared some easy-to-follow instructions for getting the extension working, so you can head on over to his github for the extension files and the tutorial. The extension demonstrates the PiP API available in recent versions of Chrome. Since these settings have been made available for the general user base on the stable channel, it is safe to assume that there are some bugs and kinks that the Chrome team would like to get out before such a release. But if you have the itch to try out the peculiarities of the bleeding edge, this is a rather straightforward way to try out one such feature.