Google Chrome is a new feature called Global Media Controls that allows you to open a small overlay window that contains playback controls and information about a YouTube video you are watching. for Windows, Linux, and Mac versions of the Chrome browser, and based on some Chrome bug reports, also appears to be in development for ChromeOS.
As first reported at Techdows.com, the latest Chrome 77 Canary build now includes a flag to turn on a new feature called Global Media Controls
When enabled, if the browser detects a controllable media session, it will display a small play button to the right of the address bar. At this point, it appears to only work with YouTube videos and it does not matter if its embedded or being watched directly on YouTube.com
When the play button is clicked, it will cause an overlay to appear that contains playback controls such as play / pause, forward, and reverse. It will also use Chrome's Media Session API to retrieve information about the video, such as the publisher, title, and artwork, and display it in the overlay.
You can see an example of the Global Media Controls overlay in the image below
In BleepingComputer's tests, this feature is quite buggy at the moment and will cause Chrome to crash soon after watching a YouTube video and opening the Global Media Controls.
Enabling Global Media Controls in Chrome Canary
If you wish to test the Global Media Controls feature, you can enable it by going to chrome: // flags and searching for global
Global Media Controls ", which you should set to Enabled . Once this flag is enabled, you will be able to access the browser which you should do to enable it.
As previously stated, a test conducted by BleepingComputer, this feature is in very early development and will crash often. If it is causing a problem, you can go back to chrome: // flags and set it b to default to disable it.