Can't uncheck “disable extensions” in Safari Develop menu

Question

After upgrading to macOS 10.13.4 my extensions in Safari were disabled. Safari Preferences Extensions tab says "Extensions can be enabled in the Develop Menu". However when I try to uncheck "disable extensions" in the Developer menu nothing happens and it stays checked.

Answer 1

I "fixed" it by deleting the 'Safari Extensions List' Keychain item and then restarting. I believe this is related to some Keychain issues I've been having because the Reset Password screen appeared after I restarted (after 5 mins of a black screen). After I reset my password my Safari Extensions were back but my Keychain had been blown out.

Answer 2

This worked for me on Safari 11--> bottom of developer menu there is "allow unsigned extensions" click that; Now go back to the developer menu and click disable extensions...

Answer 3

I fixed it by editing the plist for Safari to reset a variable that indicated extension were disabled after a reboot. "ExtensionsEnabled" was already set to YES -- and now that I fixed it I cannot find the key that was reset. Take a look in the plist for Safari.

Answer 4

In my case I had to trash all of my keychains, log out and then log in again.

Once the keychains were re-created, I could access my extensions in Safari.

I'd also note I was having difficulties logging into iCloud before trashing the keychains. This issue was also resolved at the same time. Anyone having both iCloud sign-in and Safari extensions issues both, definitely try trashing/moving your keychains.

Warning: if you're not using iCloud Keychains, you'll need some way to recover the contents of the keychains you've trashed/moved.