Apple Developer:開発者向け「Safari Technology Preview Release 48」リリース

Safari Technology PreviewApple

Apple は、開発者向けに「Safari Technology Preview Release 48」を配布しています。







今回のバージョンでは、同意なしに情報の共有を防止するためにPassword AutoFillサポート、Storage Access APIのデフォルトサポートのほか、SVG、Web API、CSS、レンダリング、Web Inspectorなどの改善や不具合が含まれています。

開発者の方は、ダウンロードページもしくはMac App Storeよりアップデート可能です。


Release 48

Password AutoFill

  • Disabled Automatic AutoFill of user names and passwords at page load to prevent sharing information without user consent

Storage Access API

  • Enabled the Storage Access API by default
  • Changed to remove access for all frames under a page when the page is closed


  • Fixed SVG lighting filter lights to use the correct coordinate system
  • Fixed feLighting that has a filter primitiveUnits=”objectBoundingBox”

Service Workers

  • Added CSP support to Service Workers
  • Changed to use no-cache fetch mode when loading main documents with location.reload()
  • Changed WebProcess to pass the registration identifier and not the worker identifier for fetch events
  • Changed to use Service Workers for documents with data URLs or blob URLs
  • Changed behavior to cancel pending script loads when the Service Worker is being terminated
  • Cleared the Cache volatile storage as a memory optimization.
  • Exposed redirect mode as “manual” for navigation loads in Service Workers
  • Enabled User Timing and Resource Timing for Service Workers
  • Fixed fetch events getting sent to a Service Worker before its state is set to “activated”
  • Fixed navigator.onLine inside Service Workers
  • Implemented the “main fetch” default referrer policy setting
  • Made Service Workers behave correctly with regards to Page Cache
  • Stopped exposing fetch and extendable events to window


  • Fixed ::first-letter to select the correct grapheme pairs
  • Fixed a blank pages except for inner iframes when pending stylesheets cause style.isNotFinal() to be true
  • Fixed image-rendering to affect the scaling of border-image
  • Fixed the special list-item counter to start from the correct number for ::before and ::after
  • Improved text appearance on some CSS spec pages


  • Changed redirected iframes loading with request.redirect=follow to fail
  • Fixed setting window.opener to null to disown its opener
  • Implemented createImageBitmap(ImageBitmap)
  • Implemented Cache API partitioning based on ClientOrigin
  • Made elements with zero width or height focusable


  • Fixed constant frame dropping during Flash video playback
  • Fixed clipping copyTexImage2D and copyTexSubImage2D
  • Fixed a visual flash caused by using font-display:fallback
  • Fixed data URL fonts that are split in the middle of an alphabet from causing random letters to disappear

Web Inspector

  • Added support for JSX (React) syntax highlighting
  • Added a content menu to the main Tab bar for showing and hiding tabs
  • Fixed the “Log Value” context menu sometimes being unavailable
  • Fixed typing a “space” in the quick console triggering a Canvas recording
  • Fixed fuzzy Capture Element screenshots
  • Fixed the Find banner sometimes not working when already populated and shown for first time on a resource
  • Fixed the “find next” and “find previous” within a resource content view does bouncing highlight when the editor scrolls
  • Fixed Layers sidebar to hide popovers when it is collapsed
  • Fixed the Export HAR context menu in the Network tab
  • Fixed DOM Tree Element selection in RTL mode
  • Fixed clicking on white space after a property sometimes placing a blank property at the wrong index in the Styles sidebar
  • Fixed long values causing bad wrapping in the Styles sidebar
  • Fixed pressing the down key to select the first item from completion list when focusing on an empty value
  • Fixed Command-G (⌘G) and Shift-Command-G (⇧⌘G) text search after closing the find banner
  • Fixed the Debugger tab to restore the selected resource on reload
  • Improved performance when dragging the recording slider in the Canvas tab
  • Improved inspector launch time, especially for systems with many fonts
  • Made the Console’s Execution Context picker stand out when it is non-default
  • Prevented properties from being semitransparent or crossed out while editing in the Styles sidebar

Web Driver

  • Implemented the Get Timeouts command


  • Changed the style of video elements when invert colors is on to preserve normal video colors
  • Implemented the updated CSS3 Speech for the speak and speak-as properties


  • Changed RTCController to disable ICE candidate filtering in case of getUserMedia based on the RTCPeerConnection origin
  • Updated WebRTC to close sockets that are marked as defunct


  • Applied poisoning to pointers in JavaScriptCore
  • Fixed for-in caching when indexed properties are added to properties on the prototype chain
  • Fixed Array storage operations that sometimes do not update the indexing mask correctly
  • Removed the arguments and caller properties for bound functions in Object.getOwnPropertyNames


  • Added poison to JavaScript object’s secrets

Bug Fixes

  • Changed the History state to be updated during client redirects with asynchronous policy decisions
  • Forbid “<” and “>” in the host name of a URL
  • Prevented recording dynamic spelling corrections while in an ephemeral browsing session
  • Reduced the precision of “high” resolution time to 1ms