Intent to prototype: Notification.actions

[Kagami Rosylight]

Summary: This adds a way for web pages to show extra action buttons for web notifications.

Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1225110

Specification: https://notifications.spec.whatwg.org/#actions

Standards Body: WHATWG

Platform coverage: Windows/macOS/Linux (Android to follow)

Preference: dom.webnotifications.actions.enabled

Other browsers:

* Blink: Shipped since version 53

* Safari: Interested (https://github.com/whatwg/notifications/pull/213#issuecomment-2233643670)

* web-platform-tests: https://wpt.fyi/results/notifications/instance.https.window.html?label=experimental&label=master&aligned (Only the basic existence is being tested as WPT currently can't simulate notification clicks: https://github.com/web-platform-tests/wpt/issues/51125)

[Randell Jesup]

Summary: Support for HTTP Compression Dictionaries 

Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1882979

Specification: https://datatracker.ietf.org/doc/draft-ietf-httpbis-compression-dictionary/
Standards Body: IETF
Platform coverage: All
Preference: network.http.dictionaries.enable

Other browsers:
* Blink: Shipped since version 130
* Safari: Positive: (https://github.com/WebKit/standards-positions/issues/160)

Link to standards-positions discussion: https://github.com/mozilla/standards-positions/issues/771

web-platform-tests: https://wpt.fyi/results/fetch/compression-dictionary?label=master&label=experimental&aligned