I have created a dual monitor wallpaper set that needs to show a specific wallpaper on each monitor as it shuffles through the files, and combining them into one stretched wallpaper doesn't work in this case because my monitors are different resolutions. The best solution I've come up with is two seperate theme files, each with the two applicable backgrounds and now I need a program to alternate between them at an interval. Does anyone have a program that can switch between theme files, or that can run monitor-specific slideshows that are in sync with one another?

Here's the first one (the green line is the monitor separation), the second one is simply a mirrored version of it.

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