KDE window focus bug - area above browser window title bar behaves as if it is part of the browser's window

I recently installed the latest version of Tor Browser on Debian Bookworm running KDE Plasma and discovered what I believe to be a bug. When the browser window is open and windowed (not maximized), the title bar has an invisible area above the window that behaves as if it were part of the window's title bar. For example, if the browser window is active and in focus, other windows and icons that are displayed behind and above it cannot be clicked on to select or shift focus to them. This invisible area seems to extend past the upper visible bounds of the browser's window border by about the size of the title bar itself. A click in this area should select whatever is behind the browser window, but it does not. Instead, it selects the browser window itself and brings it into focus, blocking selection of whatever is behind it.

Steps to reproduce:

1. Install the latest Debian Bookworm with KDE Plasma desktop.
2. Install and launch the latest Tor Browser.
3. Open any other application in a window and position the window so that it is just above Tor Browser's title bar and visible from behind when Tor Browser is brought into focus.
4. Switch focus to Tor Browser.
5. Attempt to bring the inactive window back into focus by clicking on the part of it that can be seen above Tor Browser's title bar. Tor Browser will stay in focus as if you just clicked on its own title bar as opposed to the window behind it.

I am guessing this has something to do with KDE Plasma since I have Tor Browser running on other machines with Gnome desktop without this issue. The version of Firefox that comes installed with KDE also does not have this same issue.