I am not sure what caused this, was never the fastest but now it really slow on X11 only.
Gtk4 app behavior with Wayland is normal.
Gtk3 apps run still just fine on X11.
I do use original Nvidia drivers and they are working with X11, I do see GPU resources been used by the app. (using nvidia-smi)
Running Debian Trixie.
Any ideas to fix?
It really takes several seconds for a window to show up and may be particular slow when containing a gtk-drawing-area.
While on Wayland/Hyprland it just pops up right away.