Hello, AWT Team. The bug: https://bugs.openjdk.java.net/browse/JDK-8038999 The fix: http://cr.openjdk.java.net/~pchelko/9/8038999/webrev/
After adding HTML data flavors the equals is not symmetric any more. I've also updated the hashCode, to avoid unnecessary hash collisions. Also I've fixed an annoying broken javadoc link.. With best regards. Petr.
