I installed yEd 3.22 under Debian 11. When I launch yEd the splash screen appears OK and then the main window opens.
The main window remains blank even if I operate different shortcuts, resize it, focus it in and out, etc. I do have Xwayland running. I am using Sway.
On the same machine, no problems running yEd under X11 directly (e.g. with XFCE)