WebKit Features in Safari 17.4

The feature most interesting to me, that was buried a long way down, is that iOS now supports VP9 decoding. VP9 now has 97% browser support according to CanIUse and could feasibly replace H.264 as the base video codec for the web.

(I know AV1 is superior but it has not achieved widespread support yet and requires hardware support on Apple platforms)

> custom menu commands that will appear in the File menu and the Dock context menu

This is pretty neat, but the "File" menu is sort of a vestige of a file-based approach to content management that isn't especially popular in the present era.

Web apps aren't usually file-based (e.g. Twitter, Facebook) or aren't file-based in a way that is exposed to the PWA's API (e.g. Figma). It would be better to put these in the application menu (the bold faced one with the application name to the left of "file").

> <input type="checkbox" switch>

This grieves me a bit. Because the semantics of a checkbox and switch are identical, I wish it were handled at the CSS layer and not by means of an attribute. Then you could e.g. switch from checkboxes for desktop user agents to switches for mobile UAs using a breakpoint.

Aside from the VP9 support and switch checkboxes, which others have mentioned, I'm particularly interested in the "Align content everywhere" feature, allowing you to use

  div { align-content: center; }

to get nice center-aligned content without having to use flexbox or grid.

Seems like a few interesting features to me. Shortcuts and categories definitely improve the PWA experience a bit, so they should be useful there. The switch control is long overdue, though it might be better if they standardised the styling options for ALL input elements first, since too many of them are hard to style consistently across browsers right now without using browser specific selectors. Vertical form controls are useful, and seem like a logical inclusion.

And align content inside block elements... damn, that's something that really should have been in browsers from the get go. Might finally kill the memes about centering text in CSS!

> "We built two new iOS frameworks with hundreds of new APIs to support functionality used by web browsers, including multiprocess, JIT, and advanced keyboard & touch event access — and we are pivoting WebKit to use these new frameworks."

"Used by web browsers" implies that these APIs were designed to be used by both 3rd-party rendering engines and WebKit, which is interesting. It would mean that Apple's been building OS infra for 3rd-party browsers for many years.

Glad to hear they’re rewriting their flexbox algos. Both Chrome and Safari had a huge number of issues around a decade ago, but Chrome managed to rewrite their engine and now has a very good engine. Safari was lagging behind a lot here, so it’s really welcome news

What about better adblocking? As soon as Firefox hits the stores I’ll be switching.

Really happy to see @scope is now here, though with Firefox dragging their feet (like they have with :has() and still are with @property) it still won't be usable anytime soon.

media query fullscreen ETA?