Just found the mozregression tool. That's an amazing work, I wish I had known about this much before! Minor comment: I notice the page http://mozilla.github.io/mozregression/ refers to file "C:\mozilla-build\start-l10n.bat". When I installed mozilla-build, the file that exists there is instead "start-shell-l10n.bat". Another thing I was wondering since C:\ is mentioned: does mozregression require that mozilla-build is installed to that location? I have it installed to D:\mozilla-build\, does that expect any issues?
fixed with Bug 1110222.