Intent to Remove: EME persistent-usage-record session

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Xiaohan Wang (王消寒)

Mar 8, 2021, 4:13:38 PM3/8/21
to blink-dev,

Primary eng (and PM) emails


Proposal to remove Encrypted Media Extensions (EME) persistent-usage-record session support in Blink since it’s been decided to be removed from the EME spec editor’s draft.


This feature was originally proposed by Netflix and added to the Encrypted Media Extensions (EME) spec editor’s draft. It was enabled by default in Chromium in M86 (see original “Intent to Ship”). However, since then Netflix has decided “not to use the 'persistent-usage-record' MediaKeySessionType moving forward”, and propose to remove this feature from the EME editor’s draft. This has been discussed in the W3C working group with no objections. Since Netflix hasn't started to use this feature in their web player, and no other sites are using it so far, we’d like to remove this feature to avoid the maintenance burden in the future.

Interoperability and Compatibility Risk

There is very little risk since it’s not being used by any site.

Edge: Supported, neutral to removal in spec; okay to removal in Edge.

Firefox: Not supported, no signal to removal

Safari: Support unknown, positive to removal in spec (see meeting discussion)

Alternative implementation suggestion for web developers

Not needed. This feature has not been used by any site so far. Previously Netflix was the only party interested in this feature, and they have proposed to remove this feature.

Usage information from UseCounter

This will not break any sites. UMA data shows that there’s zero usage of this feature so far.

Entry on the feature dashboard

Yoav Weiss

Mar 11, 2021, 11:58:43 AM3/11/21
to Xiaohan Wang (王消寒), blink-dev,
LGTM1 to remove

Use counters would've been nicer, but the (Google-only) data does seem convincing.
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Daniel Bratell

Mar 11, 2021, 2:57:43 PM3/11/21
to Yoav Weiss, Xiaohan Wang (王消寒), blink-dev,

Chris Harrelson

Mar 11, 2021, 3:01:46 PM3/11/21
to Daniel Bratell, Yoav Weiss, Xiaohan Wang (王消寒), blink-dev,

Xiaohan Wang (王消寒)

Mar 16, 2021, 2:34:15 PM3/16/21
to Chris Harrelson, Daniel Bratell, Yoav Weiss, blink-dev,
Thank you all for the approval!
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