--- title: Safari Technology Preview 138 Release Notes framework: safari-technology-preview-release-notes role: article role_heading: Article path: safari-technology-preview-release-notes/stp-release-138 --- # Safari Technology Preview 138 Release Notes Preview the latest web technology updates including: Web Inspector, CSS, Experimental Model Element, Media, Web Animations, WebAuthn, SVG, Web API, Service Workers, WebRTC, WebAssembly, Web Extensions, and Bug Fixes. ## Overview Overview Safari Technology Preview Release 138 is now available for download for macOS Big Sur and macOS Monterey. If you already have Safari Technology Preview installed, you can update in the Software Update pane of System Preferences on macOS. This release covers WebKit revisions 286534-286944. Note: Tab Groups do not sync in this release. Web Inspector Elements Tab Added support for Cascade Layers in the Styles sidebar (r286558) Added a swatch for align-items and align-self (r286875) Added a swatch for justify-content, justify-items, and justify-self (r286885) Added CSS variable names to property name completion list (r286890) Added an option to group CSS variables by value type in the Computed sidebar (r286876) Enabled fuzzy matching for CSS completions in the Styles sidebar (r286792, r286611) CSS Enabled :focus-visible pseudo-class by default (r286783, r286776, r286775) Enabled the resolution media query by default (r286874) Enabled the CSS Contain property by default (r286828) Changed to account for captions when flexing tables with specified sizes (r286593) Fixed perspective() less than or equal to 1px to be clamped to 1px (r286591) Fixed gap to work correctly when flex-direction: column-reverse is applied (r286654) Fixed the serialization of CSSImportRule (r286668) Unprefixed -webkit-mask (r286795) Unprefixed CSS value text-align: -webkit-match-parent (r286803) Updated color-mix() to support srgb-linear and alpha premultiplication (r286568) Experimental Model Element Added load and error events to distinguish resource load from model readiness (r286836) Media Fixed various issues with complicated rendering of VTT cues (r286743) Web Animations Added a way to run scripted animations via CustomEffect (r286555) Exposed a frameRate property to Web Animations (r286915) WebAuthn Improved WebAuthn Level 2 standards compliance by supporting the displayName (r286746) SVG Fixed transform-origin on SVG elements to take into account the transform reference box origin (r286942) Web API Changed to group radio buttons with no form owner (r286855) Fixed the range of to be reversible (r286581) Fixed an that’s been autofilled with obscured content to still be editable (r286814) Implemented AbortSignal.throwIfAborted (r286904) Improved value parsing and sanitization (r286869) Restored navigator.hardwareConcurrency (r286550) Fixed setting onselectionchange content attribute to add an event listener (r286898) Service Workers Enabled NavigationPreloadManager by default (r286540) Added support for ServiceWorker downloads (r286944) Fixed “no-cache” network error (r286655) Fixed same-site lax cookies not sent by fetch event handler after page reload (r286656) WebRTC Closed WebRTC allocation sequence shared socket in case of sequence network failure (r286539) WebAssembly Added preparation of WebAssembly.Memory imports in Wasm/ESM modules (r286703) Web Extensions Added support for changed web_accessible_resources declaration with manifest_version 3 Fixed runtime.onMessage listeners not supporting Promise returns for the reply message Show error messages for incorrect match patterns in web_accessible_resources Show error message to devtools tabs in Web Inspector when inspecting unsupported targets Show error message when the service worker background script fails to load Bug Fixes Fixed an issue introduced in Safari Technology Preview 137 where pop-up windows wouldn’t open ## See Also ### 2022 - [Safari Technology Preview 160 Release Notes](safari-technology-preview-release-notes/stp-release-160.md) - [Safari Technology Preview 159 Release Notes](safari-technology-preview-release-notes/stp-release-159.md) - [Safari Technology Preview 158 Release Notes](safari-technology-preview-release-notes/stp-release-158.md) - [Safari Technology Preview 157 Release Notes](safari-technology-preview-release-notes/stp-release-157.md) - [Safari Technology Preview 156 Release Notes](safari-technology-preview-release-notes/stp-release-156.md) - [Safari Technology Preview 155 Release Notes](safari-technology-preview-release-notes/stp-release-155.md) - [Safari Technology Preview 154 Release Notes](safari-technology-preview-release-notes/stp-release-154.md) - [Safari Technology Preview 153 Release Notes](safari-technology-preview-release-notes/stp-release-153.md) - [Safari Technology Preview 152 Release Notes](safari-technology-preview-release-notes/stp-release-152.md) - [Safari Technology Preview 151 Release Notes](safari-technology-preview-release-notes/stp-release-151.md) - [Safari Technology Preview 150 Release Notes](safari-technology-preview-release-notes/stp-release-150.md) - [Safari Technology Preview 149 Release Notes](safari-technology-preview-release-notes/stp-release-149.md) - [Safari Technology Preview 148 Release Notes](safari-technology-preview-release-notes/stp-release-148.md) - [Safari Technology Preview 147 Release Notes](safari-technology-preview-release-notes/stp-release-147.md) - [Safari Technology Preview 146 Release Notes](safari-technology-preview-release-notes/stp-release-146.md)