The fact that you can run: tcpdump -i lo0 -s 65535 -w info.pcap

Earthling enjoying life since 1985.

Mar 2, 2016

1Password sends your password across the loopback interface in clear text

The fact that you can run:

tcpdump -i lo0 -s 65535 -w info.pcap

Tells us that your system is misconfigured.

It probably happened when you installed WireShark and let it reconfigure your system. Is your current user in the "access_bpf" group?
If yes, your system is misconfigured.

Don't allow WireShark to do that.