Widevine is an encryption framework that is used for digital rights management (DRM) Its owned by Google, but used by a huge array of content creators and streaming services. It makes sure consumers cant make unauthorised copies of the media they have bought or licensed. There are three levels to the content protection: 1, 2 and 3, with level 1 being the most secure and level 3 being the least. The decrypted stream is sent to the display via a secured path like HDCP. The Chrome browser supports level 3 in all of its implementations.”]
Source: https://fidusinfosec.com/breaking-content-protection-on-streaming-websites/