To match PR #131 once/if it is merged to the spec master:
https://github.com/w3c/webcrypto/pull/131
This is a compatibility breaking change for Chromium's Web Crypto implementation, as it would mean crypto.subtle is no longer visible on insecure contexts, whereas today it is visible however all its operations fail.
(Also note that I don't propose implementing PR #131 as it currently stands, since it is marking window.crypto and not just window.crypto.subtle).
Comment 1 by bugdroid1@chromium.org
, Feb 21 2017