Created attachment 265278 [details] BT from gdb I'm using WebKitGtk+ with my own JHBuild setting: https://github.com/tanty/jhbuild-epiphany/tree/master Epiphany 3.18.0 and WebKit 2.10.3 I'm running Epiphany with the dconf key: "process-model" = "shared-secondary-process" The compilation was done with CMake args: '-DPORT=GTK -DCMAKE_BUILD_TYPE=Release -DDEVELOPER_MODE=ON -DCMAKE_C_FLAGS_DEBUG="-O0 -g1" -DCMAKE_CXX_FLAGS_DEBUG="-O0 -g1"' When visiting several pages, eventually, WebKitWebProcess receives a SIGTRAP. This bug is not reproducible in a predictable way.