Apple Releases Safari Technology Preview 135 With 120Hz Support for Smooth Scroll Animations

Apple has released Safari Technology Preview 135 which brings numerous improvements including the ability for smooth scroll animations to run at 120Hz on 120Hz displays.

Get a sneak peek at upcoming web technologies in macOS and iOS with Safari Technology Preview and experiment with these technologies in your websites and extensions.

NEW IN THIS VERSION:
Note: Tab Groups do not sync in this release.

Web Inspector and Web Driver
● Fixed "testForLinkLabels" Accessibility audit to ignore anchors if aria-hidden (r284986)
● Added support for the acceptInsecureCerts capability (r285164)

CSS
● Media queries affect Cascade Layer order (r284859)
● Enabled accent-color by default (r284634)
● Added support for small svw/svh/svmin/svmax, large lvw/lvh/lvmin/lvmax, and dynamic dvw/dvh/dvmin/dvmax viewport units (r284628)
● Added flex-basis: content support (r284440)
● Added support for contain: style for counters (r284642, r284755)
● Added support for ::before and ::after pseudo elements after ::slotted (r284973)
● Added support for more CSS properties for ::marker (r284519)
● Allowed :is and :where after all pseudo elements (r285054)
● Made :-webkit-any() a synonym of :is() (r285032)
● Fixed ::part(foo):hover (r284865)
● Serialized :part() argument as identifier (r284863)
● Fixed :host invalidation when combined with pseudo classes in descendant position (r285100)
● Prevented clamping flex base size with min-height, max-height, min-width, and max-width (r284397)
● Fixed sizing of orthogonal elements with percentage margins (r284773)
● Fixed -webkit-background-clip: text to paint correctly for inline box spanning multiple lines (r284380)
● Fixed box-shadow and text-shadow to yield float values while interpolating (r284437)
● Fixed CSS serialization affecting grid-auto-flow (r284876)
● Fixed percentages on orthogonal replaced children (r284548)
● Fixed the border-radius value from .style to be readable when it includes a var() (r285015)
● Fixed opacity to flatten when combined with transform-style: preserve-3d (r285021)

Web API
● Enabled lazy image loading by default (r284995)
● Added support for rel="noopener/noreferrer" on

elements (r284749)
● Exposed MediaCapabilities to Workers (r284443)
● Fixed anchor.relList.supports("opener") to return true (r284745)
● Fixed changing the src attribute of the img element inside an ImageDocument to trigger a load (r284901)
● Fixed document.open() and friends to use the correct document as a source for reset document's URL (r284758)
● Fixed form navigations with target="_blank" to not have an opener (r284821)
● Fixed form submission to be cancelled if the form gets detached from inside the formdata event handler (r284660)
● Fixed JavaScript URL result to be treated as UTF-8 bytes (r284934)
● Fixed Origin of opaque blob: URLs to be null instead of an empty string (r284478)
● Fixed selection extend() with no ranges to trigger an exception (r285084)
● Fixed the intrinsic size of a picture image inside a template (r284667)
● Updated appearance of