If the connection between the client and FTP server is not encrypted, Wireshark will show the username and password.

1. Start a capture in Wireshark
2. Connect to an FTP Server. Include your username and password in connection.
3. Stop the capture in Wireshark.
4. In the Wireshark filter, enter FTP.
5. In the list of packets, the unencrypted username and password should be displayed.

On the other hand, if the connection between the client and FTP server is encrypted with a SSL/TLS certficate, Wireshark will not show the username and password.