The fbomb's Emily Jane G proves why some people stereotype feminists as incapable of taking a joke:
The thing is, when you make a joke about a serious issue, in this case, sexism, you trivialise it. By turning it into something that is meant to be laughed at, you take away from the seriousness of it. When someone tells you feminists can’t take a joke, it’s time to point this out to them and it always helps to have a genuinely funny joke up your sleeve as well, to demonstrate you do recognise humour when you hear it.
I would laugh at this if it wasn't so serious. (See what I did there?) Nearly all humor is about serious things. We don't need to make jokes about trivialities; our work is already done for us. To claim that feminism should be above humor is supremely arrogant. And no one means, "You can't take a joke" literally; they mean, "You can't take a joke about your own pet issue." That isn't a feminist problem; it's a human problem.
Feminists are probably no more humorless than any other category of person. Very few people can endure humor aimed at something they consider part of their core, and Ms. G obviously ranks among the many. In fact, I'm a little skeptical that she has a sense of humor at all. Responding to "You can't take a joke" with "Oh, yeah? Let me tell you this joke!" may be one of the surest indicators of a humorless person.