I mean I should note that to even get the top panel blur here I have to flick a switch in blur my shell and also this is a bit of a non standard layout anyway but it's what I find comfy
but as it stands like, I mean I don't mind using GNOME with extensions. It's still my preferred DE of choice even if I have to tweak it a bit simply because said tweaking is a bit less hairpulling than KDE and also it like... works and is stable
I always just learn to use whatever is set by default, because the amount of time I end up spending trying to tinker with things and innevitably breaking it is more than I would save by it being absolutely perfect
It's either the X11 windows used as icons created by the applications or the override redirect windows that gnome-shell creates as parent windows for those client windows that are preventing direct scanout somehow.