Sooooo... I guessing some "Dead Baby" jokes would be tooooootally inappropriate right about now?  
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Wab
exactly my point.
Or Helen Keller jokes.Or "mommy mommy" jokes Or "Yo Mamma so" jokes etc.
Anything which subject matter might have had a negative RL experience for someone. 
Kinda narrows the list down considerably.
If your offended by a "joke" Its not necessarily because the joke itself was offensive. But rather  and more likely that the "offended" (yawn) party chooses to be offended by it.