Save on unnecessary thrown ArgumentExceptions (convenience)
Explicitly list stencil as hex with 0xXX form.
Inherit channel visibility from viewer, display inherited state

* A label is shown at the top of the pixel history showing the range
  display and visible channels. The channel visibility behaves the same as
  in the texture viewer - 2 or more and the other channels display as black
  and 1 channel displays grayscale.
Implement right click options to debug or hide failed events