---
title: Safari Technology Preview 53 Release Notes
framework: safari-technology-preview-release-notes
role: article
role_heading: Article
path: safari-technology-preview-release-notes/stp-release-53
---

# Safari Technology Preview 53 Release Notes

Preview the latest web technology updates including: Service Workers, WebRTC, Loading, Rendering, Media, Accessibility, CSS, Web API, and Web Inspector.

## Overview

Overview Safari Technology Preview Release 53 is now available for download for macOS Sierra and 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 229535-230029. This release of Safari Technology Preview has a known issue where the modal won’t appear for websites that prompt for camera or microphone access. Service Workers Changed to use one service worker process per security origin (r229735) Changed to use the same SWServer for all ephemeral sessions (r229872) Fixed promptly terminating service worker processes when they are no longer needed (r229927) Included the security origin in the service worker process name (r229878) WebRTC Added support for VCP encoder on macOS and iOS (r229920) Fixed the RTCPeerConnection constructor to throw an exception for bad configuration parameters (r229645) Fixed setting SenderTrack to null calling removeTrack with RTCRtpSender (r229587) Loading Fixed CSS mask images to be retrieved using potentially CORS-enabled fetch (r230006) Fixed loading the stylesheet when changing the <link> element rel attribute from preload to stylesheet (r229585) Rendering Fixed invalidating descendants for :nth-child and :nth-of-type pseudo classes only when needed (r229537) Fixed positioning for text with letter spacing (r229867) Media Added Fullscreen API as an Experimental Feature (r229680) Prevented SVG root from being skipped while marking percentage height descendants dirty (r229849) Accessibility Fixed table row count when role="row" is added to in DOM (r229879) CSS Fixed CSS Grid auto repeat tracks computation with definite min sizes (r229897) Web API Added a query and fragment exception to the History API’s unique origin restriction (r229540) Web Inspector Changed “Force Print Media Styles” to not persist across Web Inspector sessions (r229686) Changed to not show checkboxes for invalid properties in the Styles sidebar (r229941) Fixed the ability to add a new class by editing the class attribute in the DOM tree outline (r229744) Fixed an instance of the main WebGL canvas having no reported size in the Canvas Tab (r229659) Fixed a recording initiated by the user to properly show immediately on completion (r229620) Fixed session dividers not being added when Console tab is not visible (r229785) Fixed flashing when switching between nodes in the Styles sidebar (r229922) Fixed losing focus when editing a property while a page is being loaded (r229787) Prevented the Shift-Command-Left Arrow (⇧⌘←) and Shift-Command-Right Arrow (⇧⌘→) keys from switching tabs when focused on color picker text fields (r230001) Removed redundant tooltips (r229543)

## See Also

### 2018

- [Safari Technology Preview 72 Release Notes](safari-technology-preview-release-notes/stp-release-72.md)
- [Safari Technology Preview 71 Release Notes](safari-technology-preview-release-notes/stp-release-71.md)
- [Safari Technology Preview 70 Release Notes](safari-technology-preview-release-notes/stp-release-70.md)
- [Safari Technology Preview 69 Release Notes](safari-technology-preview-release-notes/stp-release-69.md)
- [Safari Technology Preview 68 Release Notes](safari-technology-preview-release-notes/stp-release-68.md)
- [Safari Technology Preview 67 Release Notes](safari-technology-preview-release-notes/stp-release-67.md)
- [Safari Technology Preview 66 Release Notes](safari-technology-preview-release-notes/stp-release-66.md)
- [Safari Technology Preview 65 Release Notes](safari-technology-preview-release-notes/stp-release-65.md)
- [Safari Technology Preview 64 Release Notes](safari-technology-preview-release-notes/stp-release-64.md)
- [Safari Technology Preview 63 Release Notes](safari-technology-preview-release-notes/stp-release-63.md)
- [Safari Technology Preview 62 Release Notes](safari-technology-preview-release-notes/stp-release-62.md)
- [Safari Technology Preview 61 Release Notes](safari-technology-preview-release-notes/stp-release-61.md)
- [Safari Technology Preview 60 Release Notes](safari-technology-preview-release-notes/stp-release-60.md)
- [Safari Technology Preview 59 Release Notes](safari-technology-preview-release-notes/stp-release-59.md)
- [Safari Technology Preview 58 Release Notes](safari-technology-preview-release-notes/stp-release-58.md)