Get notification count from a specific app/program

[ErikReider]

Discussed in #503

^{Originally posted by hallowelt100 January 23, 2025}
Hey everyone!

I'm currently trying to configure my lock screen on hyprlock, using swaync for displaying the total count of notifications. I do this via the swaync-client -c command.
But it would also be cool to get the notification count from a specific app, e.g. from Thunderbird (to show how many emails) or a WhatsApp client (how many new messages) to display it on my lock screen.

Is there a way to show/call the notification count only from a specific app/program?

Thanks in advance!