Specify Multiple Non-Contigous Ports Per Firewall Rule

[Ryushin]

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Is your feature request related to a problem? Please describe.
Currently it is not possible to specify multiple non-contiguous ports in a single firewall rule, other than creating a special alias specifying those ports. This makes adding firewall rules is time consuming and hard to read in the UI.

Describe the solution you like

Ideally, adding a firewall rule will let you specify the port either as comma separated rules, such as: 25,80,443,465,587,993
or even better you can specify the port and type (TCP, UDP, TCP+UDP), ICMP along Code Type (All or specific pull down for the codescode) and then add a + sign to add additional ports or ICMP types.

Describe alternatives you considered
Adding aliases for rules is time consuming and adds clutters

Additional context

Most Enterprise grade firewalls allow adding multiple ports, IPs or Machines to a single rule. Having to create an additional rule for every port or machine is time consuming and greatly clutters up the UI.

Examples:
Fortigate UI: https://www.samuraj-cz.com/gallery2/002480.png
FWBuilder UI: https://www.linux.com/images/stories/2011/fwbuilder_firewall.png

[AdSchellevis]

https://docs.opnsense.org/manual/aliases.html#ports

[Ryushin]

https://docs.opnsense.org/manual/aliases.html#ports

I'm aware that it is possible using aliases, but that is a band-aid to the problem. First I would have to create dozens and dozens of aliases which is time consuming in itself. Then in the Firewall UI, I still can't see what the ports are under the alias unless I hover my mouse over the alias. So using an Alias actually makes things worse as I can't see at a glance which ports are open in the firewall rules. It is better to create a rule for each port then so I can see what ports are being allowed.

Displaying all the ports at once in a single rule is just a better way to create a rule and a better way to see what the rules are doing in the UI.