inheritance is not supported

[masuhar]

Classes that use inheritance won't run.

• TODO: make a minimal example
• Related: it silently fails; no error messages are shown
• Possible causes: the instrumentation process inserts some code before the super call in a subclass' constructor, which is not allowed in JS.
• Other possibilities: even there are no constructors in the super and sub classes, it doesn't work. So there could be more problems.