I don't,when told Polish joke (it happened),I just politely ask them "So you basically saying that I am stupid because I am from Poland?"
As far as I can make out, you seem to want one rule for yourself and another for everyone else.
When people call you a 'dumb Polack' you complain.
When a black girl complains that people in Poland use racial slurs against her, then you tell her, "she shouldn't move the furniture".
It's either one or the other. If you have a right to complain, then so has she. If she should keep her mouth shut, then so should you.
So, should people complain about racial slurs made against them? If you are right, then so was the black girl who you told us was "a guest trying to move the furniture."