Release Notes for Safari Technology Preview 38

Safari Technology Preview Release 38 is now available for download for macOS Sierra and betas of macOS High Sierra. If you already have Safari Technology Preview installed, you can update from the Mac App Store’s Updates tab. This release covers WebKit revisions 220128-220795.

Beacon API

  • Enabled the Beacon API by default as an experimental feature (r220553)
  • Added support for CORS-preflighting (r220442)
  • Added support for CORS-preflighting on redirects (r220497)
  • Added support for connect-src CSP checks on redirects (r220549)
  • Updated sendBeacon() to rely on FetchBody instead of the whole FetchRequest (r220366)
  • Changed to use “application/octet-stream” content-type for payloads of ArrayBuffer and ArrayBufferView types (r220779)

Fetch API

  • Added support for Request keepalive getter (r220244)
  • Changed Response to keep all ResourceResponse information (r220320)
  • Implemented quota limitation for keepalive Fetch requests (r220751)

Web Payments

  • Enabled Payment Requests as an experimental feature (r220787)


  • Added support for parsing of the font-display property (r220725)
  • Implement caret-color support (r220706, r220714)
  • Added a fast path for rotate() and rotateZ() transform parsing (r220382)
  • Fixed parsing of <meta http-equiv=refresh> to allow time starting with a ‘.’ without a leading 0 (r220252)
  • Fixed a hit testing issue occurring when an SVG rect element with a non-default stroke style applied (r220717)


  • Added support for considering file extensions in the accept attribute of HTML file input elements (r220135)
  • Improved support for referrer policies (r220208)
  • Fixed the Promise resolve and reject function to have a length of 1 (r220324)
  • Fixed an early error on an ANY operator before (r220481)
  • Fixed removing an empty <li> element when inside a table cell (r220398)
  • Fixed XHR to only fire an abort event if the cancellation was requested by the client (r220731)


  • Fixed deleting the old subtitle track on src attribute change event (r220472)

Apple Pay

  • Added support for phonetic contact names (r220718)

Web Inspector

  • Added Canvas path preview when viewing a recording (r220370)
  • Changed clicking on an autocomplete suggestion to apply it, not dismiss it (r220614)
  • Removed text-shadow and gradient backgrounds (r220710)
  • Updated the filter icon in the styles sidebar (r220609)


  • Added support for interacting with <option> and <select> elements using the element click command (r220740)
  • Added support for uploading files via <input type=file> (r219874, r220115, r220135, r220147, r220222)
  • Fixed a timeout when a JavaScript alert is shown in onload handler (r220741)
  • Implemented “normal” and “eager” page load strategies from the W3C specification (r220317)
  • Updated code to use in-view center points for clicks and other automation logic (r220314)