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# Safari Technology Preview 48 Release Notes

Preview the latest web technology updates including: Password AutoFill, Storage Access API, SVG, Service Workers, CSS, Web API, Rendering, Web Inspector, Web Driver, Accessibility, WebRTC, JavaScript, WebAssembly, and bug fixes.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 48 is now [available for download](https://webkit.org/downloads/) for macOS Sierra and macOS High Sierra. If you already have Safari Technology Preview installed, you can update from the Mac App Store’s Updates tab. This release covers WebKit revisions [226358-227071](https://trac.webkit.org/log?stop_rev=226358&rev=227071&limit=999).

### 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 ([r226418](https://trac.webkit.org/changeset/226418/webkit/), [r226669](https://trac.webkit.org/changeset/226669/webkit/))
- Changed to remove access for all frames under a page when the page is closed ([r226542](https://trac.webkit.org/changeset/226542/webkit/))

### SVG

- Fixed SVG lighting filter lights to use the correct coordinate system ([r226363](https://trac.webkit.org/changeset/226363/webkit/))
- Fixed `feLighting` that has a filter `primitiveUnits="objectBoundingBox"` ([r226373](https://trac.webkit.org/changeset/226373/webkit/))

### Service Workers

- Added CSP support to Service Workers ([r226628](https://trac.webkit.org/changeset/226628/webkit/))
- Changed to use `no-cache` fetch mode when loading main documents with `location.reload()` ([r226745](https://trac.webkit.org/changeset/226745/webkit/))
- Changed WebProcess to pass the registration identifier and not the worker identifier for fetch events ([r226904](https://trac.webkit.org/changeset/226904/webkit/))
- Changed to use Service Workers for documents with data URLs or blob URLs ([r226361](https://trac.webkit.org/changeset/226361/webkit/))
- Changed behavior to cancel pending script loads when the Service Worker is being terminated ([r226398](https://trac.webkit.org/changeset/226398/webkit/))
- Cleared the Cache volatile storage as a memory optimization. ([r227052](https://trac.webkit.org/changeset/227052/webkit/))
- Exposed redirect mode as “manual” for navigation loads in Service Workers ([r226400](https://trac.webkit.org/changeset/226400/webkit/))
- Enabled User Timing and Resource Timing for Service Workers ([r226451](https://trac.webkit.org/changeset/226451/webkit/))
- Fixed `fetch` events getting sent to a Service Worker before its state is set to “activated” ([r227070](https://trac.webkit.org/changeset/227070/webkit/))
- Fixed `navigator.onLine` inside Service Workers ([r226510](https://trac.webkit.org/changeset/226510/webkit/))
- Implemented the “main fetch” default referrer policy setting ([r226397](https://trac.webkit.org/changeset/226397/webkit/))
- Made Service Workers behave correctly with regards to Page Cache ([r226677](https://trac.webkit.org/changeset/226677/webkit/))
- Stopped exposing fetch and extendable events to `window` ([r226526](https://trac.webkit.org/changeset/226526/webkit/))

### CSS

- Fixed `::first-letter` to select the correct grapheme pairs ([r226614](https://trac.webkit.org/changeset/226614/webkit/))
- Fixed a blank pages except for inner iframes when pending stylesheets cause `style.isNotFinal()` to be true ([r226653](https://trac.webkit.org/changeset/226653/webkit/))
- Fixed `image-rendering` to affect the scaling of `border-image` ([r226957](https://trac.webkit.org/changeset/226957/webkit/))
- Fixed the special list-item counter to start from the correct number for `::before` and `::after` ([r226613](https://trac.webkit.org/changeset/226613/webkit/), [r226675](https://trac.webkit.org/changeset/226675/webkit/))
- Improved text appearance on some CSS spec pages ([r227000](https://trac.webkit.org/changeset/227000/webkit/))

### Web API

- Changed redirected `iframes` loading with `request.redirect=follow` to fail ([r226792](https://trac.webkit.org/changeset/226792/webkit/))
- Fixed setting `window.opener` to `null` to disown its opener ([r226842](https://trac.webkit.org/changeset/226842/webkit/))
- Implemented `createImageBitmap(ImageBitmap)` ([r226500](https://trac.webkit.org/changeset/226500/webkit/))
- Implemented Cache API partitioning based on ClientOrigin ([r226481](https://trac.webkit.org/changeset/226481/webkit/))
- Made elements with zero width or height focusable ([r226823](https://trac.webkit.org/changeset/226823/webkit/))

### Rendering

- Fixed constant frame dropping during Flash video playback ([r226369](https://trac.webkit.org/changeset/226369/webkit/))
- Fixed clipping `copyTexImage2D` and `copyTexSubImage2D` ([r226490](https://trac.webkit.org/changeset/226490/webkit/))
- Fixed a visual flash caused by using `font-display:fallback` ([r226668](https://trac.webkit.org/changeset/226668/webkit/))
- Fixed data URL fonts that are split in the middle of an alphabet from causing random letters to disappear ([r226930](https://trac.webkit.org/changeset/226930/webkit/))

### Web Inspector

- Added support for JSX (React) syntax highlighting ([r226909](https://trac.webkit.org/changeset/226909/webkit/))
- Added a content menu to the main Tab bar for showing and hiding tabs ([r226963](https://trac.webkit.org/changeset/226963/webkit/))
- Fixed the “Log Value” context menu sometimes being unavailable ([r226394](https://trac.webkit.org/changeset/226394/webkit/))
- Fixed typing a “space” in the quick console triggering a Canvas recording ([r227008](https://trac.webkit.org/changeset/227008/webkit/))
- Fixed fuzzy Capture Element screenshots ([r226425](https://trac.webkit.org/changeset/226425/webkit/))
- Fixed the Find banner sometimes not working when already populated and shown for first time on a resource ([r226380](https://trac.webkit.org/changeset/226380/webkit/))
- Fixed the “find next” and “find previous” within a resource content view does bouncing highlight when the editor scrolls ([r226517](https://trac.webkit.org/changeset/226517/webkit/))
- Fixed Layers sidebar to hide popovers when it is collapsed ([r226671](https://trac.webkit.org/changeset/226671/webkit/))
- Fixed the Export HAR context menu in the Network tab ([r226992](https://trac.webkit.org/changeset/226992/webkit/))
- Fixed DOM Tree Element selection in RTL mode ([r226392](https://trac.webkit.org/changeset/226392/webkit/))
- Fixed clicking on white space after a property sometimes placing a blank property at the wrong index in the Styles sidebar ([r226994](https://trac.webkit.org/changeset/226994/webkit/))
- Fixed long values causing bad wrapping in the Styles sidebar ([r226995](https://trac.webkit.org/changeset/226995/webkit/))
- Fixed pressing the down key to select the first item from completion list when focusing on an empty value ([r226996](https://trac.webkit.org/changeset/226996/webkit/))
- Fixed Command-G (⌘G) and Shift-Command-G (⇧⌘G) text search after closing the find banner ([r226415](https://trac.webkit.org/changeset/226415/webkit/))
- Fixed the Debugger tab to restore the selected resource on reload ([r226374](https://trac.webkit.org/changeset/226374/webkit/))
- Improved performance when dragging the recording slider in the Canvas tab ([r226755](https://trac.webkit.org/changeset/226755/webkit/))
- Improved inspector launch time, especially for systems with many fonts ([r226371](https://trac.webkit.org/changeset/226371/webkit/))
- Made the Console’s Execution Context picker stand out when it is non-default ([r227003](https://trac.webkit.org/changeset/227003/webkit/))
- Prevented properties from being semitransparent or crossed out while editing in the Styles sidebar ([r226939](https://trac.webkit.org/changeset/226939/webkit/))

### Web Driver

- Implemented the Get Timeouts command ([r226770](https://trac.webkit.org/changeset/226770/webkit/))

### Accessibility

- Changed the style of video elements when invert colors is on to preserve normal video colors ([r226825](https://trac.webkit.org/changeset/226825/webkit/))
- Implemented the updated CSS3 Speech for the `speak` and `speak-as` properties ([r226432](https://trac.webkit.org/changeset/226432/webkit/))

### WebRTC

- Changed RTCController to disable ICE candidate filtering in case of getUserMedia based on the RTCPeerConnection origin ([r226804](https://trac.webkit.org/changeset/226804/webkit/))
- Updated WebRTC to close sockets that are marked as defunct ([r226475](https://trac.webkit.org/changeset/226475/webkit/))

### JavaScript

- Applied poisoning to pointers in JavaScriptCore ([r226530](https://trac.webkit.org/changeset/226530/webkit/))
- Fixed `for-in` caching when indexed properties are added to properties on the prototype chain ([r226767](https://trac.webkit.org/changeset/226767/webkit/))
- Fixed Array storage operations that sometimes do not update the indexing mask correctly ([r226416](https://trac.webkit.org/changeset/226416/webkit/))
- Removed the `arguments` and `caller` properties for bound functions in `Object.getOwnPropertyNames`  ([r226489](https://trac.webkit.org/changeset/226489/webkit/))

### WebAssembly

- Added poison to JavaScript object’s secrets ([r226485](https://trac.webkit.org/changeset/226485/webkit/))

### Bug Fixes

- Changed the History state to be updated during client redirects with asynchronous policy decisions ([r226929](https://trac.webkit.org/changeset/226929/webkit/))
- Forbid “<” and “>” in the host name of a URL ([r226469](https://trac.webkit.org/changeset/226469/webkit/))
- Prevented recording dynamic spelling corrections while in an ephemeral browsing session ([r226644](https://trac.webkit.org/changeset/226644/webkit/))
- Reduced the precision of “high” resolution time to 1ms ([r226495](https://trac.webkit.org/changeset/226495/webkit/))

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