--- title: Safari Technology Preview 49 Release Notes framework: safari-technology-preview-release-notes role: article role_heading: Article path: safari-technology-preview-release-notes/stp-release-49 --- # Safari Technology Preview 49 Release Notes Preview the latest web technology updates including: Service Workers, Fetch, Intelligent Tracking Prevention, CSS, Rendering, SVG, JavaScript, Web Inspector, Media, Storage, Security, Accessibility, and bug fixes. ## Overview Overview Safari Technology Preview Release 49 is now available for download 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 227071-227873. Service Workers Changed Service Workers restored from persistent storage to have “activated” state (r227153) Changed to terminate Service Workers that are unresponsive (r227174) Prevented Service Worker registrations restored from disk from being reused when the JavaScript calls register() again (r227220) Fetch Added support for ConsumeData callback when chunk data is received for Fetch response (r227870) Changed opaque being-loaded responses to clone their body (r227581) Filtered out Fetch headers from an opaque response (r227339) Fixed Fetch redirect to be compatible with “no-cors” mode (r227270) Fixed Fetch response to copy its URL from the request if it is null (r227531) Set integrity Fetch options for loading scripts and CSS (r227612) Intelligent Tracking Prevention Blocked cookies for prevalent resources without user interaction (r227103) Ensured ServiceWorker loading and requests are correctly cleared by Intelligent Tracking Prevention (r227358) Introduced debug mode as experimental feature (r227762) CSS Added support for percentages in column-gap (r227676) Added support for parsing calc() in CSS media queries (r227295) Adopted CSS WG recommended syntax changes to remove "left" and "right" in block/cross-axis alignment properties (r227432) Adopted CSS WG recommended syntax changes requiring overflow-position to precede self-position or content-position in the css-align property (r227297) Adopted support for a recent specification change removing "baseline" as a valid value for the ‘justify-content’ property (r227786) Fixed computing the scroll position of position:fixed elements when the scale is greater than 1 (r227430) Preserved original image and picture element colors when invert colors is on (r227219) Rendering Fixed the overflow of formulas for display mathematics (r227722) Optimized building the non-fast scrollable region with multiple iframes (r227396) SVG Fixed the feMorphology SVG filter to allow the radius on one axis to be 0 and still apply the effect (r227440) JavaScript Implemented trimStart and trimEnd (r227779) Relaxed line terminators in String to make JSON subset of JavaScript (r227775) Web Inspector Changed clicking on a path component that has no siblings to now select it (r227108) Changed the Layers tab to use a statically positioned layer details panel instead of a moving popover (r227244) Changed the Styles sidebar to always display CSS rules left-to-right, even when Web Inspector uses RTL layout (r227228) Fixed an issue that caused the Canvas Tab to display multiple “waiting for frames” messages (r227243) Fixed an issue that cause the record button on a Canvas Tab canvas to sometimes not appear on hover (r227155) Fixed a bug that caused the Network Tab sort indicator to hide when a sorted column is hidden and re-shown (r227667) Fixed the Network Tab’s table columns to no longer shake when scrolling at non-default zoom levels (r227463) Fixed a data corruption issue triggered by updating values in the Styles Sidebar quickly (r227370) Fixed the Styles sidebar to stop throwing exceptions when tabbing past commented out properties (r227232) Fixed the Resource Tab detail sidebar to wrap super long URLs better (r227072) Fixed Window resizing when the Web Inspector is detached from the browser (r227429) Prevented showing “Displayed Columns” when right-clicking in a table header if all columns are required (r227652) Improved the behavior of the Cookies table in the Network Tab at narrow widths (r227666) Improved Navigation Bar layout at narrow heights (r227707) Media Added support of multi keys from different sessions in CDMinstanceClearKey (r227409) Changed to resign the NowPlaying status when no media element is eligible (r227373, r227457) Changed to use existing RGB colorspace instead of creating a new one (r227094) Fixed cues for WebVTT served via HLS (r227121) Storage Added a deprecation warning to the Console when AppCache is used (r227225) Added console messages for cache storage errors like Quota (r227245) Changed to not use the storage process when loading a main resource if there is no Service Worker registered (r227161) Changed to not use the storage process when registering a Service Worker client if there is no Service Worker registered (r227242) Ensured Cache API will resolve caches.open promises in the same order as called (r227768) Fixed DOMCache data not getting properly removed when clearing data for a given origin (r227269) Increased default cache storage quota to 50MB (r227298) Security Added a policy check for targeted windows when navigating to a JavaScript URL (r227567) Added CSP post checks for Service Worker responses (r227680) Disabled access to Service Workers and the Cache API in sandboxed frames without the allow-same-origin flag (r227639) Updated frame-ancestor directive to match Content Security Policy Level 3 (r227238) Accessibility Added support for ARIA active-descendant (r227144) Added a way for VoiceOver to uniquely identify a web session (r227526) Implemented support for Graphics ARIA roles: graphics-document, graphics-object, and graphics-symbol (r227344) Prevented SVG AAM mapping from overriding ARIA role attribute in the case of SVG root (r227536) Bug Fixes Fixed the GitHub login at forums.swift.org by ensuring redirections for subresource loads can change Service Worker controllers (r227348) Fixed blob conversion and sanitization for Microsoft Word for Mac 2011 (r227351) Prevented a disallowed user-installed font from being used if its PostScript name is specified (r227776) ## See Also ### 2018 - [Safari Technology Preview 72 Release Notes](safari-technology-preview-release-notes/stp-release-72.md) - [Safari Technology Preview 71 Release Notes](safari-technology-preview-release-notes/stp-release-71.md) - [Safari Technology Preview 70 Release Notes](safari-technology-preview-release-notes/stp-release-70.md) - [Safari Technology Preview 69 Release Notes](safari-technology-preview-release-notes/stp-release-69.md) - [Safari Technology Preview 68 Release Notes](safari-technology-preview-release-notes/stp-release-68.md) - [Safari Technology Preview 67 Release Notes](safari-technology-preview-release-notes/stp-release-67.md) - [Safari Technology Preview 66 Release Notes](safari-technology-preview-release-notes/stp-release-66.md) - [Safari Technology Preview 65 Release Notes](safari-technology-preview-release-notes/stp-release-65.md) - [Safari Technology Preview 64 Release Notes](safari-technology-preview-release-notes/stp-release-64.md) - [Safari Technology Preview 63 Release Notes](safari-technology-preview-release-notes/stp-release-63.md) - [Safari Technology Preview 62 Release Notes](safari-technology-preview-release-notes/stp-release-62.md) - [Safari Technology Preview 61 Release Notes](safari-technology-preview-release-notes/stp-release-61.md) - [Safari Technology Preview 60 Release Notes](safari-technology-preview-release-notes/stp-release-60.md) - [Safari Technology Preview 59 Release Notes](safari-technology-preview-release-notes/stp-release-59.md) - [Safari Technology Preview 58 Release Notes](safari-technology-preview-release-notes/stp-release-58.md)