Release Notes for Safari Technology Preview 131

Safari Technology Preview Release 131 is now available for download for macOS Big Sur and betas of 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 280418-281002.

Note: Tab Groups do not sync in this release.

Web Inspector

  • Elements
    • Added CSS keyword completions for standard logical properties (r280588)
  • Console
    • Fixed missing execution context dropdown for contexts added after page load (r280989)
  • Network
    • Fixed sorting the Transfer Size column for failed requests changing the ordering of requests continually (r280566)


  • Changed to consider all snap areas at a given snap offset when snapping (r280527)
  • Fixed aspect ratio for replaced elements (r280471)
  • Implemented the clip value for overflow (r280509)


  • Added initial support for Cross-Origin-Embedder-Policy (COEP) (r280953)
  • Added initial support for Cross-Origin-Opener-Policy (COOP) (r280504, r280881, r280582)
  • Fixed Blob URLs changing after loading (r280824)
  • Fixed clicking an HTMLLinkElement to not trigger a navigation (r280479)
  • Fixed inaccurate Document.baseURI for iframe srcdoc documents (r280855)
  • Fixed the document’s fallback base URL to be deduced from its creator when the URL is “about:blank” (r280491)
  • Fixed <a rel="opener noopener" target="_blank"> to create a window without opener (r280933)
  • Fixed meta HTTP refresh to not navigate if the document has sandboxed automatic features browsing context flag set (r280870)
  • HTMLElement.innerText setter should convert new lines to <br> (r280482, r280541)
  • HTMLMetaElement http-equiv should not be processed in shadow trees (r280913)
  • HTMLStyleElement should create its style sheet even if its media attribute is invalid (r280910)
  • Implemented support for <dialog> element cancel event (r280703)
  • Stopped changing invalid baseURLs from loadData or loadHTMLString to “about:blank” (r280562)
  • Stopped evaluating <script> elements moved between Documents during fetching (r280924)


  • Renamed to Temporal.Now (r280506)
  • Fixed super-Latin1 white space and line terminator after regular expression literal getting misinterpreted as flags (r280825)
  • Improved RegExp performance by introducing Boyer-Moore search (r280452)
  • Made legacy RegExp constructor properties (e.g. RegExp.$1) accessors (r280460)

Platform Features

  • Fixed the start drag on image when the first piece of text inside the image is selected with Live Text (r280872)
  • Fixed the translate popover becoming detached from webpage after scrolling (r280690)


  • Fixed enter fullscreen animation interfering with auto-hiding menu bar (r280976)
  • Fixed media element to autoplay when going from background to foreground if it is initially not in viewport (r280920)

Web Audio

  • Added WebM container support for Vorbis and Opus (r280573, r280416)
  • Fixed audio buffer that may contain more frames than decoded (r280948)


  • Enabled WebRTC relay by default (r280908)
  • Enabled WebRTCPlatformUDPSocketsEnabled feature by default (r280545)
  • Introduced an experimental feature to toggle WebRTC socket proxying (r280523)

Payment Request

  • Fixed issue where additionalShippingMethods was not used when paymentMethodType was provided (r280459)


  • Added console logging to encourage the use of authenticated encryption (r280790)


  • Added support for aria-selected value changes in table cells (r280633)


  • Fixed dynamically changing HTMLStyleElement.type to change the rendering accordingly (r280909)