This bug was filed from the Socorro interface and is report bp-160256e1-f215-4c88-ba83-471dc2160810. ============================================================= Crashing Thread (34) Frame Module Signature Source 0 vcruntime140.dll memcpy f:\dd\vctools\crt\vcruntime\src\string\i386\memcpy.asm:194 1 xul.dll nsHtml5TreeBuilder::accumulateCharacters(char16_t const*, int, int) parser/html/nsHtml5TreeBuilderCppSupplement.h:960 2 xul.dll nsHtml5TreeBuilder::characters(char16_t const*, int, int) parser/html/nsHtml5TreeBuilder.cpp:454 3 xul.dll nsHtml5Tokenizer::flushChars(char16_t*, int) parser/html/nsHtml5Tokenizer.cpp:273 4 xul.dll nsHtml5Tokenizer::emitCarriageReturn(char16_t*, int) parser/html/nsHtml5Tokenizer.cpp:3473 5 xul.dll nsHtml5Tokenizer::stateLoop<nsHtml5SilentPolicy>(int, char16_t, int, char16_t*, bool, int, int) parser/html/nsHtml5Tokenizer.cpp:1831 6 xul.dll nsHtml5Tokenizer::tokenizeBuffer(nsHtml5UTF16Buffer*) parser/html/nsHtml5Tokenizer.cpp:405 7 xul.dll nsHtml5StreamParser::ParseAvailableData() parser/html/nsHtml5StreamParser.cpp:1414 8 xul.dll nsHtml5StreamParser::DoDataAvailable(unsigned char const*, unsigned int) parser/html/nsHtml5StreamParser.cpp:1111 this crash on windows seems to be regressing since firefox 48 nightly builds and in numbers since firefox 49 beta (msvc switch?). this is currently the #40 browser crash in 49.0b1 making up 0.26% of all crashes.