This task is to enable RemoteSecuritysettings.jsm in-memory, subject to preferences.

This patch:

• Classifies RemoteSecuritySettings as production.

• Add detailed logging controlled by the browser.policies.loglevel pref.

• Generally make RemoteSecuritySettings match other services better.

• Move to hex-encoded hashes to match Kinto.

• Adds RemoteSecuritySettings to blocklist-clients. This may not be the
  permanent home.

• Adds a preference for how many certs to download at once.

• Adds an Observer interface.

  (This makes the tests more predictable, but it also avoids having a
  duplicate call when the full "sync" is called.)

https://hg.mozilla.org/mozilla-central/rev/839decca3577

Is this worth a mention in the 72 release notes?

Maybe so. :)

Release Note Request (optional, but appreciated)
[Why is this notable]
In Beta 72 we're pre-populating all disclosed Intermediate CA certificates for all Firefox users. We haven't set this to ride the whole train yet because the previous attempt uncovered issues with the underlying RKV data-store when it hit Beta, and we're being conservative. We will probably roll to release in 73.

[Affects Firefox for Android]:
Not yet enabled for Android

[Suggested wording]:
Firefox 72 will, in the background, locally cache all trusted Web PKI Certificate Authority certificates known to Mozilla. This will improve HTTPS compatibility with misconfigured web servers.

[Links (documentation, blog post, etc)]:
Not yet. We will when we are prepared to enable for riding the trains, probably shortly after Beta goes to 72.

Regarding comment 7, this got pushed back to at least 74 per the latest Trello update.

Adding to the draft 75beta release notes.