I am trying to get util/doh/tests/robot.html to run on Firefox 52, IcedTea 7, JRE 8, on debian.
I’ve included jessie-backports and installed openjdk-8-jre. IcedTea itweb-settings correctly identifies the JVM.

In the JavaScript console I get:

Here is the log from the java console:

Any help would be much appreciated.