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Este artigo diz principalmente que será mais integrado:
it can ensure that no window can appear atop the screensaver surface, it can properly detect idling and grabs already, and has complete control over the screen. Unlike the X design, there wouldn't even need to be a screensaver "window" that's on top but the compositor could just keep painting a black screen.
Parece que foi implementado há 3 meses . Ele escreve isso:
This also causes properly written animating clients to stop rendering, and we can hit zero CPU usage, even when there is a screensaver active.