# Safari Technology Preview 153 Release Notes Preview the latest web technology updates including: Web Inspector, CSS, JavaScript, Rendering, Screen Capture, Media, WebGL2, Web API, Accessibility, and WebDriver. ## Overview [Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 153 is now [available for download](https://webkit.org/downloads/) for macOS Monterey 12.3 or later and macOS Ventura beta. If you already have Safari Technology Preview installed, you can update in the Software Update pane of System Preferences on macOS Monterey, or System Settings under General → Software Update on macOS Ventura. This release includes WebKit changes between: [253169@main…253847@main](https://github.com/WebKit/WebKit/compare/c99710d339f40f15752909d03e542d67877a4785...1799d27c20bc2f8be4f1ea37b62799a5339dcdb1) **Note:** Shared Tab Groups and syncing for Tab Groups, Website Settings, and Web Extensions are not enabled in this release. ### Web Inspector - Sources Tab - Added support for Symbolic Breakpoints ([253374@main](https://commits.webkit.org/253374@main), [253791@main](https://commits.webkit.org/253791@main)) - Elements Tab - Added a way to control what badges are shown in the main DOM tree ([253579@main](https://commits.webkit.org/253579@main)) - Added Event badges for nodes that directly have event listeners in the main DOM tree ([253727@main](https://commits.webkit.org/253727@main)) - Changed the Computed panel to no longer show the Variables section when the selected element has no CSS variables ([253562@main](https://commits.webkit.org/253562@main)) - Changed the Computed panel to sort prefixed properties below non-prefixed properties ([253789@main](https://commits.webkit.org/253789@main)) - Changed the Computed panel to only show inline swatches that actually preview the value ([253214@main](https://commits.webkit.org/253214@main)) - Network Tab - Fixed highlighting only the initiated resources when a row is hovered ([253476@main](https://commits.webkit.org/253476@main)) ### CSS - Added support for background images on `::first-line` ([253553@main](https://commits.webkit.org/253553@main)) - Added right-to-left direction support for `text-overflow: ellipsis` ([253689@main](https://commits.webkit.org/253689@main)) - Implemented `forced-colors` media query ([253290@main](https://commits.webkit.org/253290@main)) - Fixed text-decoration location for superscripts when the text string contains both superscript and regular text ([253406@main](https://commits.webkit.org/253406@main)) - Fixed handling of layout and paint containment with internal ruby boxes ([253354@main](https://commits.webkit.org/253354@main)) - Fixed `:has(:lang(~))` invalidation with dynamic changes ([253764@main](https://commits.webkit.org/253764@main)) - Fixed `@supports` to not work if “not”, “or”, or “and” isn’t follow by a space ([253194@main](https://commits.webkit.org/253194@main)) - Fixed handling of `font-variant: normal` and `font-variant: none` shorthand ([253731@main](https://commits.webkit.org/253731@main)) - Fixed behavior of `cursor: auto` over links ([253685@main](https://commits.webkit.org/253685@main)) - Fixed `color-scheme` to not propagate to the viewport background if set on the `` ([253565@main](https://commits.webkit.org/253565@main)) - Fixed tiled layer flicker when an animation ends ([253549@main](https://commits.webkit.org/253549@main)) - Fixed the transferred `min` and `max` sizes to be constrained by defined sizes ([253262@main](https://commits.webkit.org/253262@main)) - Fixed pseudo-elements not treated as ASCII case-insensitive ([253631@main](https://commits.webkit.org/253631@main)) - Fixed the title of non-CSS stylesheets to be not preferred ([253632@main](https://commits.webkit.org/253632@main)) - Fixed `input[type=search]` to hide icons when `appearance: textfield` is set ([253691@main](https://commits.webkit.org/253691@main)) - Included `aspect-ratio` when calculating inline `min-content` size and add `min-content` block computation ([253740@main](https://commits.webkit.org/253740@main)) - Renamed initial value of `color-scheme` from `auto` to `normal` ([253659@main](https://commits.webkit.org/253659@main)) - Used `align-content` when calculating the static position of absolutely-positioned flexbox children ([253389@main](https://commits.webkit.org/253389@main)) - Used logical `top`, `bottom`, and `height` when computing the available height for an out-of-flow block ([253312@main](https://commits.webkit.org/253312@main)) ### JavaScript - Implemented import-assertion and JSON module ([253234@main](https://commits.webkit.org/253234@main)) - Implemented `Temporal.PlainDateTime` to the extent of the current PlainDate implementation (Behind the `--useTemporal` flag) ([253623@main](https://commits.webkit.org/253623@main)) - Fixed not generating `import.meta` object if it is not referenced ([253636@main](https://commits.webkit.org/253636@main)) - Optimized `async` and `await` and microtask queue ([253651@main](https://commits.webkit.org/253651@main)) - Optimized `Promise.all` ([253716@main](https://commits.webkit.org/253716@main)) - Added support for WebAssembly GC recursion groups ([253491@main](https://commits.webkit.org/253491@main)) ### Rendering - Changed to not generate text runs for empty text content ([253569@main](https://commits.webkit.org/253569@main)) - Fixed `text-overflow: ellipsis` to change the text content to render ([253607@main](https://commits.webkit.org/253607@main)) - Fixed `text-overflow: ellipsis` to not affect geometries ([253650@main](https://commits.webkit.org/253650@main)) - Fixed underline thickness to align with device pixels ([253182@main](https://commits.webkit.org/253182@main)) - Stopped propagating scroll-snap style from `` to viewport ([253430@main](https://commits.webkit.org/253430@main)) ### Screen Capture - Changed to reject the `getDisplayMedia` prompt if the system picker times out ([253260@main](https://commits.webkit.org/253260@main)) ### Media - Included explicit `!important` `min`, `max` properties, and explicit `width` and `height` for full-screen elements ([253790@main](https://commits.webkit.org/253790@main)) - Fixed `MediaRecorder.stop()` firing an additional `dataavailable` event with bytes after `MediaRecorder.pause()` ([253529@main](https://commits.webkit.org/253529@main)) - Fixed audio pitch changes on enabling or disabling the mic capture ([253673@main](https://commits.webkit.org/253673@main)) - Fixed screen recording in a background tab working for only about a minute ([253769@main](https://commits.webkit.org/253769@main)) ### WebGL2 - Stopped applying the buffer offset twice in `getBufferSubData` ([253175@main](https://commits.webkit.org/253175@main)) ### Web API - Implemented the Imperative Slot API ([253187@main](https://commits.webkit.org/253187@main), [253198@main](https://commits.webkit.org/253198@main), [253199@main](https://commits.webkit.org/253199@main), [253202@main](https://commits.webkit.org/253202@main), [253266@main](https://commits.webkit.org/253266@main), [253320@main](https://commits.webkit.org/253320@main), [253359@main](https://commits.webkit.org/253359@main), [253365@main](https://commits.webkit.org/253365@main), [253392@main](https://commits.webkit.org/253392@main), [253396@main](https://commits.webkit.org/253396@main), [253402@main](https://commits.webkit.org/253402@main)) - Implemented full search for text directives for Scroll to Text Fragment spec ([253383@main](https://commits.webkit.org/253383@main)) - Added `Set-Cookie` as a forbidden header name ([253325@main](https://commits.webkit.org/253325@main)) - Added generic media query parser and evaluator ([253298@main](https://commits.webkit.org/253298@main)) - Added support to the Permissions API for dedicated workers ([253447@main](https://commits.webkit.org/253447@main)) - Added support to the Permissions API for Service Workers and Shared Workers ([253752@main](https://commits.webkit.org/253752@main)) - Added way to get parent inline box to the inline iterator ([253304@main](https://commits.webkit.org/253304@main)) - Added `box-sizing: border-box` to `table` in the User-Agent stylesheet ([253581@main](https://commits.webkit.org/253581@main)) - Fixed blob URLs with a fragment from opaque origins cannot be loaded ([253498@main](https://commits.webkit.org/253498@main)) - Fixed ignored charset of blobs ([253458@main](https://commits.webkit.org/253458@main)) - Fixed composited canvas element to update the layer configuration after creating a WebGL context ([253231@main](https://commits.webkit.org/253231@main)) - Fixed position elements should layout relative to transformed container ([253809@main](https://commits.webkit.org/253809@main)) - Fixed `Navigator.share()` rejecting with the wrong exception when called multiple times ([253419@main](https://commits.webkit.org/253419@main)) - Fixed `iframe srcdoc` with a quirky doctype to use no-quirks mode ([253326@main](https://commits.webkit.org/253326@main)) - Fixed `input[type=search]` preferred content width to not include decorations ([253595@main](https://commits.webkit.org/253595@main)) - Fixed `Permissions.query` to return “prompt“ for opaque origins ([253785@main](https://commits.webkit.org/253785@main)) - Fixed scheduling a navigation to a Blob URL to keep the URL alive until the navigation actually occurs ([253435@main](https://commits.webkit.org/253435@main)) - Fixed forms with a disabled submit button from being posted with the Enter key ([253228@main](https://commits.webkit.org/253228@main)) - Fixed the HTML parser to ignore starting `` tags in the “in head noscript” state ([253489@main](https://commits.webkit.org/253489@main)) - Fixed the HTML parser’s foster-parenting algorithm to not require foster parents to be elements ([253504@main](https://commits.webkit.org/253504@main)) - Fixed the HTML parser’s adoption agency algorithm to not reverse the order of nodes ([253505@main](https://commits.webkit.org/253505@main)) - Fixed an issue where `data-x-2=""` is not included in the dataset if it’s the only data attribute ([253625@main](https://commits.webkit.org/253625@main)) ### Accessibility - Added support for the ARIA 1.3 property `aria-description` ([253184@main](https://commits.webkit.org/253184@main)) - Fixed updating accessibility objects role after a dynamic `contenteditable` change ([253630@main](https://commits.webkit.org/253630@main)) ### WebDriver - Added support for Wheel input source and actions ([253578@main](https://commits.webkit.org/253578@main)) - Added support for “Get Computed Role” and “Get Computed Label” commands ([253732@main](https://commits.webkit.org/253732@main)) - 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