For the purpose of window rules, is there any way to differentiate two windows that are otherwise identical?

Finally made the move to Wayland and [this protocol regarding window positions](https://gitlab.freedesktop.org/wayland/wayland-protocols/-/merge_requests/18) isn't done yet, so I was looking into doing it manually for a few cases.

One of those was getting Firefox "Picture-in-Picture" windows tiling up again instead of just spawning in the center of my screen and needing resized/repositioned, but I can't seem to find a way to make window rules see PIP 1 and PIP 2/etc as different; my only idea so far was to use the " <2>" KDE appends to duplicate titles in an exact title match but it doesn't seem to matter as far as window rules are concerned.