I would like to configure the Unassigned ports into "disabled" port profile, instead of "default", how can I configure this?

By default, unassigned ports in the Mist UI are using the "default" port profile.

In this case, the unassigned ports use the "default" port profile because it is the same default setting for interfaces in JunOS; therefore, Mist does the same.

This behavior helps maintain consistency between Mist and non-Mist switches.

Now, you can manually change any port (or port range) to use the "disabled" port profile. To do so, you can follow the steps below:

Go to Switches > List > (select switch) > Port Configuration > Add Port Configuration > Port IDs > Click in the icon to select ports > Select the ports you want to disable > Configuration Profile > Select "disabled" > Then hit the blue check mark. > finally Save.

For Example:

1:

2:

3:

4:

5: