Apple - Is there a way to configure password auto-generation in Safari?

I'm not aware of any way to do this in Safari, but you can always generate new passwords in System Preferences instead:

  • Open Users and Groups preferences.
  • Go as if to change your password.
  • Click the key button next to the "New password" field. This will open the password generator.
  • It generates a password for you, but you can edit it or even type in your own password, and it'll give you an estimate of how strong it is.
  • Drag the password into the text entry field. (You can copy and paste it if you're not concerned about clipboard managers storing it, or clipboard-sniffing malware, but drag-and-dropping isn't any harder anyway.)
    • You can actually drag and drop text like this in almost any app! You need to click and hold for a moment before you start to drag, or it'll think you're trying to select.

You can also do this in Keychain Access – just hit ⌘N to create a new keychain item and click the key button, and it shows the same password generator.