Visual bug on Linux KDE

Sometimes when I open a private window, it would visually bug. I cannot click the icons in the visual area because it is not really there. So I have to click where it should have been, but obviously this is a visual bug. Notice that this only happens on KDE but not on GNOME. I spoke to one of the KDE developers and he said following:

“Heroic Game Launcher and Brave are both 3rd-party apps running in XWayland mode. This means they have control over where their windows are placed and they’re doing it wrong. GNOME might not suffer from this problem because perhaps they forcibly place XWayland-windows according to the native Wayland window positioning; it would be a very GNOME thing to do. Technically this is breaking a part of XWayland that apps may be relying on, though.”

I have uploaded a screenshot of the visual bug.