This is a request for WebKit's position on the "EME MediaKeySession Closed Reason" proposal: *Links* - W3C EME spec issue/explainer: https://github.com/w3c/encrypted-media/issues/473 - W3C EME spec Pull Request: https://github.com/w3c/encrypted-media/pull/487 - Previous Media Working Group meeting discussion on this topic (with Jer Noble): https://lists.w3.org/Archives/Public/public-media-wg/2020Sep/0004.html Summary A MediaKeySessionClosedReason is proposed to indicate the reason for EME MediaKeySession closure, and the `closed` attribute would return a `Promise<MediaKeySessionClosedReason>` instead of the current `Promise<void>`. Motivation The current EME spec says "the CDM may close a session at any point, such as when the session is no longer needed or when system resources are lost". However, there's no way to specify the exact reason for session closure. In some cases, this is part of normal user flow, e.g. user close laptop lid to put the device into sleep mode, where the player should resume playback. In some other cases, this is due to some unrecoverable fatal error. This proposal updates the `closed` attribute on MediaKeySession to provide a MediaKeySessionClosedReason so that the JavaScript player can handle session closure differently based on the reasons. *Contact email* xhwang at chromium.org Looking forward to your feedback! Best, Xiaohan