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april fools should span an entire week
(programming.dev)
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.
You can do pranks any day of the year tho. For instance, September 3rd is “shit in my cats litter box and see if my wife notices the difference” day.