Does JLabel has a html text preferred size problem?
Specifically with a \ in the html sometimes i see the line after missing, if the first line was long enough to overflow (only sometimes? unexpected?) being word breaked. So the line after that poor \n dissapears. I will try to make a test case, but you know how it is with test cases for platform graphics bugs. I'm posting this in the hope someone has a clue (subclassing the JTooltipUI is not acceptable).