The GeForce Experience GameStream Co-op browser plugin was built using Google's Chrome App framework. Google has announced that it is transitioning from Chrome Apps for PC at an unspecified date this year. We plan to support Co-op as long as Google supports the PC Chrome App. Once Google finishes their transition, Co-op may no longer function.
Note: Gamestream to SHIELD does not use the Chrome App framework and remains fully supported by GeForce Experience.