Sorry about my Waypipe misunderstanding.
vncserver I configured that way, so of course. I just didn’t expect it to connect to Wayland.

If invoking xfce4-session works, it means you are doing so over vnc, not waypipe.

It does work over Waypipe. You can even see in my screenshot that on the remote machine it shows Waypipe as the WM.
The remote is running Debian 13, with multi-user.target set as default target to keep the GUI from starting. XFCE version is 4.20.1.

Using Waypipe, which proxies Wayland program GUIs to my local computer, just like ssh -X, but with Wayland, and it actually works over the internet (read: high latency).

I didn’t know XFCE supported Wayland , so I casually ran vncserver, which launched xfce4-session, except that it attached itself to the Wayland display (proxied to my local machine) rather than X display of TigerVNC. And here come the full XFCE right to my local machine (which is running Plasma).

Only if the machine is on LAN. I am running with 250ms here.

No, I was not using VNC. VNC xstartup script just launched xfce4-session which connected to Waypipe rather than Xtigervnc.

It does integrate itself to KDE nicely. Even with virtual desktops. And it even properly does the animations. Downside is, I can’t access the original desktop on my laptop while it’s running. Peek at desktop also shows XFCE.
Here’s the cube switcher, showing XFCE instead:

Probably snaps too.

Yeah, Gemini is… interesting. It said it’s a “one-way route” for the human.