Windows screen savers are designed to use the full desktop area and, by default, span across all connected monitors. The built-in configuration options in Windows 11 allow choosing the screen saver type, its settings, wait time, and whether to show the logon screen on resume, but do not provide a way to restrict a screen saver to only one of multiple displays.
For multi-monitor behavior, the platform guidance is that a screen saver either:
- Displays on all monitors when built with the current screen saver framework, or
- Must be custom-coded (using the multiple monitor APIs) if different behavior per monitor is required.
With the standard Windows 11 screen saver settings, it is not possible to limit the screen saver image to only the middle/main display while leaving the others unaffected.
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