Stop Safari asking for my password when autofilling my password

Solution 1:

I just ran into this problem as well, I found that it was only happening on my MacBook with the Touch ID fingerprint scanner.

If this is true for you as well then you can turn the password prompt off by going to System Preferences > Touch ID and unchecking the box next to Password Autofill.

Solution 2:

Well, you could wear an Apple Watch, but I'm guessing you won't like that answer. ;-)

BTW, I've been seeing the same behavior and consider it strange, possibly a bug introduced in macOS 10.14.4

Safari should only be asking for your password once, if you haven't used the autofill feature or authenticated against your Apple ID in 15 minutes.

If it's asking for your macOS login password, that's because your key chain has been locked. Try changing your login password then rebooting. Hopefully your keychain will remain unlocked after you log in again.