Deprecations and removals in Chrome 66
Current thinking on setting device options is to use the constrainable pattern . Consequently this property was removed from the ImageCapture specification . Since this method appears to have little to no use on production websites, it is being removed. A replacement method is not available at this time.
Service worker: disallow CORS responses for same-origin requests
Previous versions of the service worker specification allowed a service worker to return a CORS response to a same-origin request. The thinking was that the service worker could read from a CORS response to create a completely synthetic response. In spite of this, the original request URL was maintained in the response. So
outerResponse.url exactly equaled
innerResponse.url exactly equaled
A recent change to the Fetch specification requires that
Response.url be exposed if it is present. A consequence of this is scenarios in which
self.location.href returns a different origin than
self.origin. To avoid this, service workers are no longer allowed to return CORS responses for same origin requests.
For a longer discussion on this change, see the issue filed against the Fetch specification in November 2017.
WebAudio: dezippering removed
Web audio originally shipped with dezippering support. When an AudioParam value was set directly with the value setter, the value was not updated immediately. Instead, an exponential smoother was applied with a time constant of about 10 ms so that the change was done smoothly, limiting glitches. It was never specified which parameters had smoothing and what the time constant was. It wasn’t even obvious if the actual time constant was the appropriate value.
After much discussion , the working group removed dezippering from the spec. Now, the value is changed immediately when set. In place of dezippering, it is recommended that developers use the existing
AudioParam.setTargetAtTime() method to do the dezippering, giving you full control on when to apply it, how fast to change, and on which parameters should be smoothed.
Removing this reduces developer confusion which audio parameters support dezippering.
CSS position values with three parts deprecated
Recently specifications have required that new properties accepting position values not support values with three parts. It's believed this approach makes processing shorthand syntax easier. The current version of the CSS Values and Units Module applies this requirement to all CSS position values. As of Chrome 66, three-part position values are deprecated. Removal is expected in Chrome 68, around July 2018.
Methods document.createTouch(), document.createTouchList() are deprecated
TouchEvent() constructor has been supported in Chrome since version 48. To comply with the specification,
document.createTouchList() are now deprecated.