Release Notes for Safari Technology Preview 219

May 14, 2025

by Jon Davis

Safari Technology Preview Release 219 is now available for download for macOS Sequoia and macOS Sonoma. If you already have Safari Technology Preview installed, you can update it in System Settings under General → Software Update.

This release includes WebKit changes between: 293899@main…294487@main.

Canvas

Resolved Issues

  • Fixed re-drawing a canvas with relative width when the parent element is resized. (294401@main) (121996660)

CSS

New Features

  • Added support for the margin-trim: block inline syntax for trimming in both directions. (294190@main) (141784069)

JavaScript

Resolved Issues

  • Fixed Array.prototype.pop to throw an exception when the array is frozen. (293907@main) (141805240)
  • Fixed f() = 1 behavior with other engines when not using strict mode. (293996@main) (149831750)

Media

Resolved Issues

  • Fixed SVG images with sub-resources to appear correctly when used in MediaSession. (294334@main) (148089535)

Rendering

Resolved Issues

  • Fixed an issue where feMerge incorrectly positioned HTML elements when merging the same feMergeNode multiple times. (294088@main) (149431216)
  • Fixed an issue in determining when a flex item should be used for percentage resolution during intrinsic width computation. (293901@main) (149615295)

Web API

Resolved Issues

  • Fixed an overly broad fullscreen exit trigger by restricting it to only text-entry elements gaining focus, preventing non-text input types from causing unexpected fullscreen exits. (294284@main) (136726993)

Web Extensions

Resolved Issues

  • Fixed 'allowAllRequests' for declarativeNetRequest. (294041@main) (72203692)
  • Fixed a non-fatal webRequest error for non-persistent background content. (294142@main) (150051544)

WebRTC

New Features

  • Added support for RTCEncodedAudioFrame and RTCEncodedVideoFrame constructors. (293951@main) (149541424)