message: Avoid double file extensions in Crowdin filenames
  Don't create filenames like .pot.po or .xliff.xliff. Do keep names like
  Sparkle.strings.xliff where there's meaningful information about the
  original file type.
diff: @@ -624,11 +624,16 @@ private:
  else if (ext == "pot")
  {
  // POT files are natively supported, but need to be opened as PO to see translations
  - localFileName.SetFullName(localFileName.GetFullName() + ".po");
  + localFileName.SetExt("po");
  + }
  + else if (ext == "xliff" || ext == "xlf")
  + {
  + // Do nothing, we don't want to use double-extension like .xliff.xliff
  }
  else
  {
  - // Everything else is exported as XLIFF
  + // Everything else is exported as XLIFF and we do want, at least for now, to keep
  + // the old extension for clarity, e.g. *.strings.xliff or *.rc.xliff
  localFileName.SetFullName(localFileName.GetFullName() + ".xliff");
  }
  