hello, most of these crashes appear to be caused by the Wondershare Video Converter Ultimate extension/software that is running on your computer. please uninstall that program! in addition there also appears to be malicious software/adware active on the pc (the ''DatamngrHlpFF31.dll'' file is showing up in the loaded modules), so please perform a full scan of your system with the various tools listed at [[Troubleshoot Firefox issues caused by malware]]