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xkcd #2897: Light Leap Years
(imgs.xkcd.com)
Alt text:
When Pope Gregory XIII briefly shortened the light-year in 1582, it led to navigational chaos and the loss of several Papal starships.
I would argue that nearly no one finds this one funny but many found this one funny
The OP comic is less accessible than the empiricism one, so the target audience is smaller, some of the smaller audience comics required one knew Firefly, open source memes, and Corey Doctorow. When you're in the target group the comics are especially hilarious
Some have fallen flat for me until I looked up XKCD explained, since I have very low knowledge of pop culture. I wouldn't say those aren't funny, I say I don't get them