Software Update: Google Chrome 77.0.3865.75

Feature Policy Control over Document.domain
the document domain policy governs access to document.domain. It is enabled by default, and, if disabled, attempting to set document.domain will throw an error.

Layout Instability Monitoring
Adds the LayoutShift interface to the Performance API, allowing developers to monitor changes to a DOM element’s on-screen position.

Limit the “referer” Header’s Length to 4kB
Strips the referer header down to an origin when it’s size exceeds 4kB. Servers will often behave in unexpected ways when presented with an overly-long referer header. This is unfortunate, because referer is one header whose length attackers generally retain control over when generating no-cors requests.

Limit registerProtocolHandler() url Argument to http/https
The registerProtocolHandler() now only accepts URLs with http or https schemes. Because the intent of the API is to allow an endpoint to handle something like an SMS message, for example, it doesn’t make much sense for handlers to be data URLs, blob URLs, and so on.

New Features for Intl.NumberFormat
This change improves Intl.NumberFormat by adding support for measurement units, currency and sign display policies, and scientific and compact notation.

Overscroll Behavior Logical Longhands
Adds CSS flow relative properties for controlling overscroll behavior through logical dimensions. flow-relative properties are those that are interpreted relative to the flow of content. The new properties are overscroll-behavior-inline and overscroll-behavior-block.

PerformanceObserverInit Buffered Flag
Adds a buffered flag to observer.observe() so that PerformanceObserver can receive entries created before the call is executed.

WebRTC
RTCPeerConnection.onicecandidateerror Adds the incecandidateerror event which provides detailed information about WebRTC ICE candidate gathering failures, including the ones defined by STUN (RFC5389) and TURN (RFC5766). Diagnosing ICE connectivity issues without access to detailed gathering failures can be a challenge. Support for ICE candidate errors is targeted towards better connectivity troubleshooting and network diagnostics. RTCPeerConnection.restartIce() Adds a method for triggering an ICE restart which causes a WebRTC connection to try to reconnect. This feature is already available in Chrome by passing the iceRestart argument to createOffer(). restartIce() is a version of this method that works regardless of signalingState.

Service Workers
Preserve Request Priorities through Service Worker Preserves a request’s original priority when it passes through a service worker. Previously, all requests going through a service worker would get “High” priority. This means render-blocking style sheets would have their priority clamped, while less important resources would get boosted. Service Workers Support Basic HTTP Authentication Displays HTTP authentication dialog boxes even if the request was from a service worker. This shows the native login dialog shown when an HTTP 401 response is received.

Stop Action for Media Sessions
Adds Stop as a MediaSessionAction for calls to MediaSession.setActionHandler(). An action is an event tied specifically to a common media function such as pause or play. The stop action handler is called when the site should stop the playback and clear the state if appropriate. Samples are available on GitHub.

Web Payments: Throw a TypeError on Invalid “basic-card” Data
The PaymentRequest constructor now throws a TypeError when invalid supportedNetworks or supportedTypes are specified for basic card payment. See Deprecations and Removals for an additional Web Payments update item. For more about recent web payments updates, see W3C Payment API changes in Chrome 77.

Interoperability Improvements
Support Step Timing Functions jump-start|end|both|none
Adds support for a richer set of step animations. Firefox already supports jump-* step timing functions. The step timing functions jump-both, jump-none, jump-start and jump-end were introduced to the spec for easing functions in 2018. Two of these, jump-start and jump-end are aliases for start and end. The remaining two provide increased flexibility for step transitions by enabling step functions in which both or neither endpoint has a discontinuous step. Previously, one and only one of the two endpoints could have a step discontinuity. Adding support in Chromium improves cross-browser interoperability.

white-space: break-spaces
Adds the break spaces value for the white-space property which specifies that any sequence of preserved white space that would otherwise overflow a line and hang (as per the CSS Text Module spec’s Trimming and Positioning rules) must be broken. With white-space: pre-wrap it’s possible to wrap and preserve white space sequences in the middle of a text line. However, if there is a sequence at the end of the line, it either collapses or hangs, maybe overflowing its box area. The new value overflow-wrap: break-spaces allows authors to wrap and preserve these white space sequences. This can be also useful for textarea or contenteditable elements, so that white space sequences added by spacebar press events are handled properly and generate line breaks if needed. Finally, there is an ongoing effort to enhance interoperability of the line breaking CSS properties (white-space, word-break and overflow-wrap) and this new value was defined precisely to achieve that.

Deprecations, and Removals
Card Issuer Networks as Payment Method Names
remotes support for calling PaymentRequest with card issuer networks (eg, “visa”, “amex”, “mastercard”) in the supportedMethods field.

Deprecate Web MIDI Use on Insecure Origins
Web MIDI use is classified into two groups: non-privilege use, and privilege use with sysex permission. Until Chrome 77, only the latter use prompts users for permission. To reduce security concerns, permissions will always be requested regardless of sysex use. This means that using Web MIDI on secure origins will no longer be allowed.

Deprecate WebVR 1.1 API
This API is now deprecated in Chrome, being replaced by the WebXR Device API, which is expected to ship in Chrome 78. The WebVR Origin Trial ended on July 24, 2018. WebVR was never enabled by default in Chrome, and was never ratified as a web standard. the WebXR Device API is the replacement API for WebVR. Removing WebVR from Chrome allows us to focus on the future of WebXR and remove the maintenance burden of WebVR, as well as reaffirm that Chrome is committed to WebXR as the future for building immersive web-based experiences. Removal is expected in Chrome 79.