A few things that stand out:

* Enabled WebAuthN on macOS! - Web Authentication API on MDN [0]: "an extension of the Credential Management API that enables strong authentication with public key cryptography, enabling passwordless authentication and/or secure second-factor authentication without SMS texts." I think Safari was the last major holdout on this API, so this might be huge. Could anyone that has had experience with this API share any thoughts and experiences?

* `document.hasStorageAccess()` - Storage Access API on MDN [1]: "provides a way for embedded, cross-origin content to gain unrestricted access to storage that it would normally only have access to in a first-party context (we refer to this as an origin’s first-party storage)." The feature originated from Apple: Introducing Storage Access API [2]; it's still considered experimental and is only supported by Firefox and Safari. Skimming through the related WHATWG HTML issue [3], the discussion seems worth reading if you're interested in a bit of the reasoning that goes into designing these APIs.

* `line-break: anywhere` - From Chrome Platform Status [4]: "allows soft wrapping around every typographic character unit, including around any punctuation character or preserved spaces, or in the middles of words."

[0] https://developer.mozilla.org/en-US/docs/Web/API/Web_Authent...

[1] https://developer.mozilla.org/en-US/docs/Web/API/Storage_Acc...

[2] https://webkit.org/blog/8124/introducing-storage-access-api/

[3] https://github.com/whatwg/html/issues/3338

[4] https://www.chromestatus.com/feature/5668660729348096

Proper WebGL 2.0 support in Safari seems MIA despite occasional tweets and mailing list posts implying otherwise. Seems it's going to hang out half-baked in the "Develop > Experimental Features" menu indefinitely.

WWDC is just around the corner

Why wouldn't it have been ramped up as part of the Technology Preview releases?

This is nice but it's disappointing that Apple's browser improvements are influenced by the cadence of WWDC conferences.

The feature set of the browsing engine isn’t though. It’s on a roughly 6 monthly schedule where changes for the technology previews are released to the wider public.

The last big release was 12.1 last March, far removed from the next WWDC in June (for a release in September).

I only said influenced. You're responding to a claim I didn't make.

They don't make it easy to switch to the preview. None of my Safari settings seem to have been imported, all my bookmarks are gone and the 'import bookmarks from Firefox' doesn't work either :(

Something is wrong with your configuration. For me, both the release version and the tech preview share settings just fine.

Making changes to the one will cause them to be applied in the other.

I found a way of importing bookmarks: Run 'normal' Safari and preview Safari at the same time, 'view bookmarks' in both, and then dragging the favorites top level across from old to new app worked!

Simpler way is to use iCloud sync with Safari.

I have that turned on and I still didn't get my bookmarks. Hopefully my empty bookmarks folder in Safari Preview didn't get synced across all my devices before I fixed it...

iCloud sync between the two is very iffy almost always does not work, for compatibility reasons.

Will you see new bookmarks (or reading list items) created in STP on, say, your iphone’s mobile safari, though?

I’ve used STP for years and never had to import bookmarks or anything like that.

I suspect that the basic problem is related to how the tech previews interact with things like security updates -- essentially STP ships without a full release process, and isn't updated in line with major security fixes -- which together probably warrants an STP not having the required rights to pull in access to safari preferences, and just from a reliability PoV restrict their desire to pull in other browser preferences.

Copy ~/Library/Safari to ~/Library/SafariTechnologyPreview if you're okay with overwriting existing settings of STP.

Has anyone been able to get WebAuthN working on Safari with FIDO2 keys? I just downloaded this preview, tried several WebAuthn example sites that work fine on Chrome and Firefox, but on Safari nothing happens and my Yubikey 5 doesn’t even light up.

Those sites are probably doing useragent filtering. Force a Chrome or Firefox useragent in the Developer menu and try again.

I have a solokey (solokeys.com) that supports FIDO2/U2F.

I can get Dropbox and https://webauthn.me/ to work with the key in Safari without any trouble.

I cannot get Google or Github to work with the key. I tried changing user-agent string and using Firefox, no luck.

in my experience sites still gate on UA rather than available functionality, so maybe UA checks are involved?

I know some sites that do this but it’s definitely not working on sites where no UA gate is involved, the WebAuthN request is being made but my Yubikey never lights up

When will Safari support FIDO U2F keys?

Just tested Google 2FA login with a Solokey. Works perfectly. https://solokeys.com

Are there any chants or rituals I'm supposed to know about, because I can't get my solokey to work with Google or Github?

It did work with Dropbox, so that's nice.

Seriously? I'll try it out right now.

Still no push notifications?

Is actually anybody using web notifications? Despite being prompted hundreds (thousands?) times - before I disabled it via about:config and dom.webnotifications.enabled - I never opted in for it.