Answer
The window manager removes the condition that forcible retrieval of resources is forbidden.
Work Step by Step
"Analysis of deadlock has revealed that it cannot occur unless all three of the following conditions are satisfied:
1. There is competition for non-sharable resources.
2. The resources are requested on a partial basis; that is, having received some resources, a process will return later to request more.
3. Once a resource has been allocated, it cannot be forcibly retrieved."
The window manager removes the condition that forcible retrieval of resources is forbidden (the third of the 3 conditions).
