There's no comprehensive list, and it would be impossible to make one. Anything we do might potentially offend somebody, somewhere, and nobody can understand every little nuance of every culture and every individual's life experiences.

Like, what if you're wearing a green sweater, and somebody was once assaulted by a person wearing a green sweater and your sweater really upsets somebody? There's no way we possibly could have known.

It's really complicated sometimes.

Here's the thing though: it's not always complicated!

Sexual comments around women we don't know? Totally an easy one. We should avoid those comments. Some women don't care, some find them hilarious, but a significant portion of women really don't want to hear that kind of talk from men they don't know.

We don't have to be mind readers, or even particularly sensitive to understand this. (In fact, we don't even have to understand it. Just memorize it.)

Yes, my common sense tells what is appropriate and what isn't in public. You have to keep in mind that every single person has something that they are sensitive about and they usually have a legitimate reason for that. Thew problem is a lot of people don't have a filter between their brain and their mouth. They just say whatever is on their mind without thinking. And this is what can happen when you do that. I basically don't say anything in public that could be offensive to people in general but yes I also take the crowd i'm with into consideration as well, like with your situation.

And of course, before anyone says it.... Its not about being "PC" its about not being a douchebag.

Of course its being PC since this is exactly how PC is defined. You don't get to wish away the label simply because you don't like it, especially when you've just repeated the definition.

I can always tell when I'm talking to someone with a strong filter and it always makes me feel uncomfortable. They don't seem genuine, they don't seem honest, they don't seem real. I wonder how they are really like when relaxed with their filters down. What if they really are a douchebag? I've met plenty of people who filter heavily but are still basically sociopaths.

I've heard there is now corporate training on how to have a strong filter without letting other people know that you have one, by intentionally and strategically letting out noticeable but forgivable gaffes at certain points to make it appear as if you are genuine.

Argh! Ack! I am offended by your use of the word douchebag. You did not stop to think. Where is your filter? Argh. Ack.

"Common sense" isn't as "common as we like to think, is it? "Public" is a state of mind.

Adria was overhearing a conversation not meant for her ears. It was her error.

You do realize that your logic is largely flawed.

You can never make a joke that isn't offensive to at least one person somewhere one way or another, unless you give up joking altogether. You said it yourself "every single person has something that they are sensitive about". It could be as legitimately rightful as sexist jokes.. or as unrightful as joking about anything else entirely, maybe my mother was run over by a bus driver.. does that mean that you cannot joke about bus drivers next to me?.. Well actually yes, but only "if" you knew of my particular situation and in this case he did not.

The general rules of decency dictate that you steer away from the generally offensive jokes in your respective crowd and the joke he made was not such, it was if anything something that fits that crowd perfectly. I for one had no idea what it was supposed to mean outside the tech lingo but unlike her I was not in a PyCon conference.