Safari and Safari Technology Preview completely broken after upgrading from Ventura 13.6.5 to Sonoma‌ 14.4

Hi, three days ago I made the mistake of upgrading to Sonoma 14.4. After the upgrade, I tried to open Safari, and was met with a popup window/prompt asking whether I want to open the window/tabs from the previous session. Regardless of whichever option I chose, Safari just froze completely.

I tried force quitting, and starting Safari whilst holding the Shift key (which should open a fresh session), but that also didn't work. Following that, I tried starting Safari in Safe Mode, but that also did not work. I should note that at this time Safari Technology Preview was working fine.

After half a day of trying to troubleshoot this, an Apple Mail extension (Mailbutler) prompted me to sign in to my Google account, and that process triggered a small window/session of Safari to open (with the Gmail login page). Finally, I was able to access the Safari menubar settings.

I went into the menubar settings, deactivated all 20 or so of my extensions, deleted all website data, deleted cache for both of my two profiles, quit Safari, and then tried to open Safari hoping all of that would have fixed it. This time, Safari just froze immediatly without giving me to option of restoring the previous session or not.

I tried accessing the Safari menubar settings several times using the Apple Mail/Mailbutler/Gmail login loophole, and after some trial and error I discovered that I was able to open a window with my secondary profile ("Work"), without any problem. I also tried to open a window with my default profile ("Personal"), multiple times - but this always caused Safari to freeze/become unresponsive.

At this point, I assumed that the default profile must have been "corrupt" in some way (I have no idea how that could even happen though). I've called Apple Support, and Apple Developer Support, 3-4 times in the last couple of days trying to get help, but as soon as they hear that I am on Sonoma Beta, they just give up and say that they have no obligation to assist customers with beta versions (despite having AppleCare), and the only recommendation they can give is to format the computer and do a complete Time Machine backup restore..

After having spoken to Apple Support, I've tried to reinstall Sonoma three time. I have tried to selectively, and completely, delete the Safari library files (and then restoring backups when noticing that it hasn't worked). I have also tried to use Cookie (by SweetP Productions) to delete various Safari files, hoping that might fix the issue. Finally, I've tried to delete all of the Safari library files (with backups), and then using Time Machine I've attempted to restore all the files that were used by Safari prior to the Sonoma upgrade (this also didn't work).

Earlier today I decided to simply give up, and just forget about Safari. After all, Safari Technology Preview was working fine, and I could just use that until Apple pushes a new Sonoma update (which would hopefully repair Safari). But after half a day of using Safari Technology Preview, I now seem to have run into the exact same problem.

Right now, both Safari and Safari Technology Preview are completely broken. Both programs become unresponsive the moment they are launched. As Apple provides the dmg file for Safari Technology Preview on their website, I figured I should at least be able to simply reinstall the app and that would solve the problem. But reinstalling Safari Technology Preview doesn't seem to do anything at all.

Long story short - I have somehow managed to break both Safari and Safari Technology Preview after upgrading from Ventura 13.6.5 to Sonoma‌ 14.4. Apple are telling me they won't provide any help as I am using beta software. If anyone has any suggestions or ideas for how to solve this (for example, deleting any of the library/support files?), please don't hesitate to share. Thanks

Safari and Safari Technology Preview completely broken after upgrading from Ventura 13.6.5 to Sonoma‌ 14.4
 
 
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