This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
MediaKeySession.expiration read-only property returns the time after which the keys in the current session can no longer be used to decrypt media data, or NaN if no such time exists. This value is determined by the CDM and measured in milliseconds since January 1, 1970, UTC. This value may change during a session lifetime, such as when an action triggers the start of a window.
var expirationTime = mediaKeySessionObj.expiration;
|Encrypted Media Extensions
The definition of 'expiration' in that specification.
|Working Draft||Initial definition|
|Feature||Chrome||Edge||Firefox (Gecko)||Internet Explorer||Opera||Safari (WebKit)|
|Feature||Android||Android Webview||Edge||Firefox Mobile (Gecko)||Firefox OS||IE Mobile||Opera Mobile||Safari Mobile||Chrome for Android|
|Basic support||No support||43.0||(Yes)||?||?||?||?||?||42.0|