mozregression 0.41 fixes bug 1185756, which caused the following warning on Windows:

WindowsError: [Error 32] The process cannot access the file
because it is being used by another process

Also, mozregression is now more tolerant when facing failures like a build not installable or a crash from the tested application (see bug 1192485).

And finally, when using mozregression with a custom profile it won’t be modified anymore (see bug 999009). This was a longstanding bug - thanks to Jonathan Pigree for his help in fixing it!