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OS X Mavericks: Window Locations Lost
This discussion involves window locations, but the issues seem to be related to changes in support for dual-display setups and do not seem to be an issue on single-display systems.
For reference, a dual-display configuration. Discussion continues below.

Behavioral bugs
Instability in behavior is not a serious problem, but it wastes time and becomes annoying when working long hours.
Might the window-position amnesia issues be related to the new “App Napp” feature?
Starting Safari forgets the window location
Since I always use Safari on the portrait-orientation display to the left of the main screen (as shown above), this behavior is a constant nuisance: I have to drag the Safari window to my 2nd display EVERY time it starts up.
The strange this is that Safari works properly for a while (quit and restart and the window remembers its place). But some time later, it reverts to bad behavior (back on the main screen). Sometimes it pops up here, or there, and it all seems semi-random.
Yet Google Chrome works properly in this scenario not. Except that invoking it from the command line fixed the problem. And then the problem comes back—some loose screws are present.
Activity Monitor also forgets its window location
The position of the CPU history window exhibits the same erratic behavior as Safari windows.
Option-clicking from one app to another to hide the first
Still does not work if the current app is in full screen mode (should hide window, does not). This was broken in previous OS releases also.
Apple 16.2" MacBook Pro with M1 Max Chip (Late 2021, Space Gray)
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