Release Notes for Safari Technology Preview 87

Safari Technology Preview Release 87 is now available for download for macOS Mojave and the macOS Catalina beta. 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 246691-247047.


  • Changed openDatabase to return an empty object when WebSQL is disabled (r246707)
  • Added an experimental behavior to prevent a 5 second delay for initial paint on pages that are using Google’s anti-flicker optimization when content blockers are enabled (r246764)

Web Sockets

  • Added support for sending blob messages when using web sockets platform APIs (r246964)

Payment Request

  • Changed to set state to Closed when show() is called during an active session (r246863)

Experimental Web Shading Language (WHLSL)


  • Fixed incorrect clipping with overflow: scroll inside overflow: hidden with border-radius (r246845)
  • Fixed the preview of a <picture> element to match the element bounds (r246695)


  • Made WebGPU enabled only on Mojave and later (r246888)

Web Inspector

  • Implemented console.countReset (r246850)
  • Implemented console.timeLog (r246798)
  • Added additional demo audits for other WebInspectorAudit functions (r247042)
  • Enable the Show Shadow DOM navigation item by default in the Elements tab (r246821)

Known Issues

  • Open tabs are blank on initial launch after upgrading to Safari Technology Preview 87 and loading all tabs from the last session. To correct this behavior, reload open tabs or relaunch Safari Technology Preview.