“In days of King Jehoram, Edom revolted against the rule of Judah. They set up a king of their own. Then King Jehoram crossed over with his commanders and all his chariots. He set out by night. He attacked the Edomites who had surrounded him and his chariot commanders. So Edom has been in revolt against the rule of Judah to this day. At that time, Libnah also revolted from his rule, because he had forsaken Yahweh, the God of his ancestors.”
This is once again based on 2 Kings, chapter 8. The revolt of Edom, which was south east of Judah on the other side of the Jordan River, was successful. There is no mention of the town Zair here. King Jehoram attacked or seemed to be successful, but there is no indication of what happened. The area of Libnah which was south west of Judah also revolted successfully against this southern King Jehoram. Here it says that Libnah revolted because King Jehoram was not true to Yahweh. Things did not go well with him as king. Edom was still in revolt at the time of this biblical writer, which would be about 500 years later. This looks like an attempt to blame the loss of Edom on King Jehoram.
Eugene Finnegan Bible Project 