I do not recognize this crash signature. When I check the comments submitted by users with their crash reports over the past month, I can't help noticing they are all from the zh-CN locale: https://crash-stats.mozilla.com/signature/?product=Firefox&signature=CreateProcessAsUserW&date=%3E%3D2017-10-27T01%3A22%3A35.000Z&date=%3C2017-11-27T00%3A22%3A35.000Z#comments There may be something unique to that build which is causing this issue, but I don't have a good idea of what it is. Have you noticed any pattern? Perhaps you can check this forum for any suggestions: http://mozilla.com.cn/forum-55-1.html