That's probably DRM protected content, it's not Javascript hack but a mecahnism that's built in deeper. A high level overview of how it works on Android is her

That's probably DRM protected content, it's not Javascript hack but a mecahnism that's built in deeper. A high level overview of how it works on Android is here(the secure texture part): https://source.android.com/devices/graphics/arch-st#st_vid_play https://source.android.com/devices/graphics/arch-st#st_vid_p... I'm not sure what the implementation is on Chrome/Desktop; probably something similar.