Apple Developer:開発者向けに「Safari Technology Preview Release 46」配布

Safari Technology PreviewApple

Apple は、開発者向けに「Safari Technology Preview Release 46」を配布しました。







ブラウザが Web ページとは別にバックグラウンドで実行するスクリプト「Service Workers」がデフォルトで有効になったほか、セキュリティUI面では、セキュリティで保護されていないページのパスワードやクレジットカードフォームと対話するときにスマート検索フィールドに警告が表示されます。


Release 46

Service Workers

  • Made Service Workers enabled by default
  • Exposed self.registration inside Service Workers
  • Removed HTTP headers added by CachedResource and CachedResourceLoader in Service Worker fetch
  • Rejected promises in the ServiceWorkers API when calling objects inside of detached frames
  • Yielded image content from a CacheStorage.add(url) network request
  • Changed the Fetch event header filtering to only apply in CORS-mode
  • Handled self.skipWaiting() inside Service Workers
  • Removed XMLHttpRequest from being exposed to Service Workers
  • Implemented clients.get() and clients.getAll()
  • Supported container.register() and registration.unregister() inside Service Workers
  • Targeted the Service Worker’s scope URL for remote inspection metadata
  • Made navigation requests to use navigate fetch mode
  • Activated IndexedDB and Web Sockets in Service Workers
  • Supported container.getRegistration() and container.getRegistrations() inside Service Workers
  • Added support for serviceWorker.postMessage() and serviceWorkerRegistration.update() inside of Service Workers
  • Added support for the Service Worker client unloading algorithm
  • Added support for FetchEvent.clientId
  • Addressed various issues inspecting Service Workers
  • Included support for Service Worker generated redirections
  • Populated self.registration.installing, self.registration.waiting, and inside Service Workers

Security UI

  • Added a warning in the Smart Search field when interacting with password or credit card forms on non-secure pages


  • Froze the user-agent string to reduce web compatibility risk and to prevent its use for fingerprinting


  • Fixed small or clipped controls caused by scale() transforms on <video> elements
  • Clamped automatic minimum size in CSS grid if the min() track sizing function is auto
  • Implemented alignment for absolute positioned CSS grid items


  • Fixed an often blank <object type=”image/svg+xml” data=”foo.svg”> in an HTML-page
  • Fixed missing layer content when animating elements on-screen
  • Implemented transferToImageBitmap for WebGL offscreen canvas objects
  • Prevented viewport unit values from being affected by zooming with ⌘- or ⌘+

Storage Access API

  • Implemented frame-specific access in the network storage session layer
  • Made document.hasStorageAccess a function and always allow access for same-origin iframes

Web Inspector

  • Made Computed a top-level sidebar panel in the Elements tab
  • Added the ability to filter rules and add new style rules in the redesigned Styles sidebar
  • Added display of related pseudo-elements in the Styles sidebar
  • Changed the behavior of pressing delete in an empty value field of a newly added property to focus on the name field in the Styles sidebar
  • Fixed CSS properties not being removed in the Styles sidebar after deleting their values
  • Fixed details section headers overlapping the Classes container in the Computed Styles panel
  • Fixed adding a new property after a property without trailing semicolon in the Styles sidebar
  • Prevented adding a property before or after the first property from becoming appended to the end in the Styles sidebar
  • Fixed the filter bar in the Console tab sometimes not appearing and cases where clear console doesn’t always work
  • Fixed content views for resources loaded through XHR and Fetch to reflect the declared MIME-type
  • Fixed the Remote Web Inspector window to restore the last used window size
  • Fixed spurious warnings shown for commands that changed pixel contents in the Canvas tab
  • Improved the initial user interface experience in the Canvas tab
  • Fixed an issue that caused Safari to hang after toggling “Allow Web Inspector” setting on an attached iOS device.

Web Assembly

  • Fixed postMessage to allow a WebAssembly module to postMessage to and from an iframe
  • Fixed a bug where we would incorrectly throw stack overflow errors

Web Driver

  • Added support for handling user prompts shown while executing scripts
  • Fixed link and partial links queries to work in XHTML documents
  • Fixed computeElementLayout to correctly translate iframe client coordinates to main frame coordinates
  • Fixed a regression that causes page screenshots to only contain the viewport
  • Fixed an issue where safaridriver would quit after trying to close a window when no windows remain open


  • Corrected the recursive tail call optimisation on closures
  • Implemented BigInt literals and JSBigInt
  • Implemented a more optimized WeakMap and WeakSet
  • Optimized Object.assign by single transition acceleration


  • Added support for the decoding=”sync” or decoding=”async” attribute on images
  • Enabled use of the VCP H264 encoder for platforms that support it
  • Fixed the cursor not becoming visible after exiting full screen video
  • Included “video/*” in image request Accept header if the browser supports video media in image contexts


  • Changed to allow AudioContext to start when getUserMedia is on
  • Fixed an issue where getUserMedia is resolving before the document knows it is capturing
  • Prevented the display from going to sleep when playing WebRTC video tracks