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Platform: <!-- Example: Ubuntu Desktop 17.04 amd64 -->

GPU, drivers, and screen setup: <!-- Example: NVidia GTX 670, nvidia-drivers 381.09, two monitors configured side-by-side with xrandr -->

Compton version: <!-- Example: 0.1~beta2+20150922-1 from the official repository -->

Compton configuration: <!-- Put the configuration on your preferred pastebin service and place the link here, or directly paste it to the bottom of the issue. -->

### Steps of reproduction

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### Expected behavior

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### Current Behavior & Other details

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