They sent a letter to the US ambassador complaining about the initiative in Congress to change the definition of "Palestinian refugee" to be consistent with the definition of every other kind of refugee.
The protesters stated that "this resolution would be a burden on Jordan and the countries where there are camps for the Palestinians in terms of expenditures" and that the international community must pay for the Palestinian Arabs expenses since it created the problem.
They also held signs saying that the "right to return" to Palestins is sacred, and that one way or another, they will return (and, of course, destroy Israel.)
They further said that they will continue to protest as long as anyone dares to contest their refugee status.
Keep in mind that the vast majority of Palestinian Arabs in Jordan are full citizens of the state and would not be considered refugees by any definition except the skewed "working definition" of UNRWA that is accepted by the world without question for only this one group of people.