Yes me too. I just stream my whole monitor and add black bars to hide unneeded decorations and like my open apps etc.

But I didnt try single apps, is that a Pipewire thing? I do a ton of QGis tutorials and QGis needs to run through XWayland to not break when moving toolbars, afaik.

Like, QGis opens a ton of new windows, not sure if the KDE plasma portal supports capturing them too automatically.