Post any defects you find in the released or beta versions of the ImageMagick software here. Include the ImageMagick version, OS, and any command-line required to reproduce the problem. Got a patch for a bug? Post it here.
But for any release after that (ignoring 6901, which is known to be bad), the resulting histogram image is only viewable by IM. All other tools seem to say it is corrupt and cannot open it or show nothing. This includes Mac Preview and Safari, Firefox and Chrome browsers.