[Question] Single module execution on multiple monitors

[apiraino]

As a test, I wrote a custom module that just prints a semi-random number:

    "custom/counter": {
        "exec": "bash -c 'echo $RANDOM'"
    },

Then I start Waybar (under Sway) with waybar -b bar-0.

When I have two monitors connected, Waybar shows 2 different numbers on the monitors. I expected to see the same number on both monitors.

I'm probably missing how Waybar works: although I see many child processes, I thought Waybar runs as a single process and each module is executed just once.

Can anyone help me understand that? Is there a way to run a module exactly once per Waybar instance?

thanks