Open Radar

 
Summary:
When a Mac running 10.9 has two or more displays connected, if you have an application with windows on more than one screen, application-switching, whether by command-tab or clicking on the dock icon of the application you want to switch to, causes the window on the screen with the Dock to be activated, rather than the most recently used window (the behavior in System 7-Mac OS X 10.8), or even the most recently used window on the currently active screen, which was the case using Spaces in previous versions of OS X. This is unbelievably annoying.

Steps to Reproduce:
1. Connect a second display to your Mac. 
2. Open a Cocoa application with multiple windows, such as Terminal.app.
3. Put one or more windows on one display, and one or more on the other. 
4. Open another application. 
5. cmnd-tab to, or click the dock icon of the first application to switch to it. 

Expected Results:
The application should be switched to and the most recently used window in the app should be active. 

Actual Results:
The application is switched to and the window on the screen with the Dock is active.

Version:
10.9/13A603

Notes:
Notes:
Regression from System 7-Mac OS X 10.8. 
Workaround: continually move the dock to the display you primarily work on. This is a terrible workaround.