This is my favorite PDF reader of all time. I am not 100% sure how FOSS freindly they are but this has the best feature set of any PDF viewer/reader I have used to date.

https://www.foxitsoftware.com/products/pdf-reader/ 

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A mouse trap, placed on top of your alarm clock, will prevent you from rolling over and going back to sleep after you hit the snooze button.

Stephen