Read the endpoint before guessing a service

A listener waits for incoming traffic at an endpoint. Keep an address,
port and transport when identifying an endpoint; these shortened rows
assume one host and omit its address. TCP and UDP use separate port
spaces even when the digits match. A client also has its own port.

Dynamic ports range from 49152 through 65535. The later client examples
use that range. A customary association such as HTTP with 80/tcp or
HTTPS with 443/tcp does not establish an actual listener or protocol.
The supplied row is evidence for this card, not a scan or vulnerability.

Original fictional listener card. Not output from ss.

Worked row
Service        Listener   Name that does not decide the port
status page    8081/tcp   HTTP is often associated with 80/tcp
The client on this row uses 8081.

Activity rows
Service           Listener   Note
notes page        9090/tcp   the stated listener for the page
notes datagrams   9090/udp   same number, other transport, not the page
https customary   443/tcp    no row says a listener is here

Predict before reading the check. Check: the notes page client uses 9090.

Separate row used by the question
Service     Listener
demo HTTP   8080/tcp